Migrate info from INSTALL.md into doc/QuickStart.md

Move most information regarding configuring ngIRCd into the
doc/QuickStart.md document, only describe building and installing ngIRCd
in the INSTALL.md file. Don't duplicate content!

Add references where this makes sense.

INSTALL.md

@@ -1,18 +1,20 @@
 # [ngIRCd](https://ngircd.barton.de) - Internet Relay Chat Server
 
-This document explains how to install and configure ngIRCd, the lightweight
+This document explains how to install, the lightweight Internet Relay Chat
-Internet Relay Chat (IRC) server.
+(IRC) server.
 
 The first section lists noteworthy changes to earlier releases; you definitely
 should read this when upgrading your setup! But you can skip over this section
 when you do a fresh installation.
 
-All the subsequent sections describe the steps required to install and
+All the subsequent sections describe the steps required to build and install
-configure ngIRCd.
+ngIRCd from sources. The information given here is not relevant when you are
+using packages provided by your operating system vendor or third-party
+repositories.
 
 Please see the file `doc/QuickStart.md` in the `doc/` directory and
-[online](https://ngircd.barton.de/doc/QuickStart.md) on the homepage for some
+[online](https://ngircd.barton.de/doc/QuickStart.md) on the homepage for
-configuration examples.
+information about configuring ngIRCd, including some configuration examples.
 
 ## Upgrade Information
 
@@ -362,38 +364,14 @@ standard locations.
 
 ## Configuration
 
-Please have a look at the `ngircd(8)` and `ngircd.conf(5)` manual pages for
+Please see the file `doc/QuickStart.md` in the `doc/` directory and
+[online](https://ngircd.barton.de/doc/QuickStart.md) on the homepage for
+information about configuring ngIRCd, including some configuration examples.
+
+And have a look at the `ngircd(8)` and `ngircd.conf(5)` manual pages for
 details and all possible command line and configuration options -- **and don't
 forget to run `ngircd --configtest` to validate your configuration file!**
 
-The file `doc/QuickStart.md` in the `doc/` directory and
-[online](https://ngircd.barton.de/doc/QuickStart.md) on the homepage has some
-configuration examples, you should take a look :-)
-
-After installing ngIRCd, a sample configuration file will be set up (if it
-does not exist already). By default, when installing from sources, the file is
-named `/usr/local/etc/ngircd.conf` (other common names, especially for
-distribution packages, are `/etc/ngircd.conf` or `/etc/ngircd/ngircd.conf`).
-
-You can find the template of the sample configuration file in the `doc/`
-directory as `sample-ngircd.conf` and
-[online](https://ngircd.barton.de/doc/sample-ngircd.conf) on the homepage. It
-contains all available options.
-
-In the sample configuration file, there are comments beginning with `#` *or*
-`;` -- this is only for the better understanding of the file, both comment
-styles are equal.
-
-The file is separated in five blocks: *[Global]*, *[Features]*, *[Operator]*,
-*[Server]*, and *[Channel]*.
-
-In the *[Global]* section, there is the main configuration like the server
-name and the ports, on which the server should be listening. Options in
-the *[Features]* section enable or disable functionality in the daemon.
-IRC operators of this server are defined in *[Operator]* blocks, remote
-servers are configured in *[Server]* sections, and *[Channel]* blocks are
-used to configure pre-defined ("persistent") IRC channels.
-
 ### Manual Pages Online
 
 - Daemon: [ngircd.8](https://manpages.debian.org/ngircd.8)

doc/QuickStart.md

@@ -19,8 +19,12 @@ everything was parsed as expected!
 
 ### Configuration File and Drop-in Directory
 
-The `ngircd --configtest` command shows the name of the default configuration
+After installing ngIRCd, a sample configuration file should have been set up if
-file, too. For example `/etc/ngircd/ngircd.conf`.
+none existed already. By default, when installing from sources, the file is
+named `/usr/local/etc/ngircd.conf` (other common names, especially for
+distribution packages, are `/etc/ngircd.conf` or `/etc/ngircd/ngircd.conf`).
+Run the command `ngircd --configtest` to check the name of the configuration
+file which is used by default on your local system.
 
 In addition, ngIRCd supports further configuration file snippets in a "drop-in"
 directory which is configured with the `IncludeDir` variable in the `[Options]`
@@ -32,6 +36,11 @@ ore more new files in this include directory, overriding the defaults as
 needed. This way you don't get any clashes when updating ngIRCd to newer
 releases.
 
+You can find the template of the sample configuration file in the `doc/`
+directory as `sample-ngircd.conf` and
+[online](https://ngircd.barton.de/doc/sample-ngircd.conf) on the homepage. It
+contains all available options.
+
 ## Configuration File Syntax
 
 The configuration consists of sections and parameters.
@@ -45,6 +54,11 @@ Section and parameter names are not case sensitive.
 Please see the `ngircd.conf`(5) manual page for an in-depth description of the
 configuration file, its syntax and all supported configuration options.
 
+The sample configuration file uses comments beginning with `#` *or* `;` -- this
+is only for the better understanding of the file, both comment styles are
+equal. The lines commented out with `;` show example or default settings,
+whereas the lines using `#` are descriptions of the options.
+
 ## Simple Single-Instance Server
 
 A good starting point is to configure a valid (and unique!) IRC server name