Move all defaulting-of-CAP_FOO to sysconfig.h.

- The phrase `#ifdef CAP_` should never appear anywhere.

- The phrase `#ifndef CAP_` should appear only in sysconfig.h.

- The phrases `#if CAP_` and `#if !CAP_` may appear wherever,
    as long as "sysconfig.h" is included first.

The rules for `CAP_FOO` equally apply to `ISFOO`.

There are many one-off macros still tested with `#ifdef`,
including `HAVE_ACHIEVEMENTS`, `PRINT_ACHIEVEMENTS`,
`FAKEWEB`, `FAKE_SDL`, `EASY`, and `WHATEVER`. I don't
have much grasp on what these are used for or how they're
configured, so I'm leaving them alone.

sysconfig.h

@@ -63,6 +63,14 @@
 #define ISMINI 0
 #endif
 
+#ifndef CAP_NCONF
+#define CAP_NCONF 0
+#endif
+
+#ifndef CAP_DRAW
+#define CAP_DRAW 0
+#endif
+
 #ifndef CAP_XGD
 #define CAP_XGD (ISANDROID || ISFAKEMOBILE)
 #endif
@@ -85,6 +93,10 @@
 #define NOLICENSE ISSTEAM
 #endif
 
+#ifndef CAP_VERTEXBUFFER
+#define CAP_VERTEXBUFFER (ISWEB)
+#endif
+
 #ifndef CAP_SHADER
 #define CAP_SHADER CAP_GL
 #endif
@@ -153,6 +165,10 @@
 #define CAP_SURFACE CAP_RUG
 #endif
 
+#ifndef CAP_KUEN_MAP
+#define CAP_KUEN_MAP 0
+#endif
+
 #ifndef CAP_EDIT
 #define CAP_EDIT (CAP_FILES && !ISWEB && !ISMINI)
 #endif
@@ -197,6 +213,10 @@
 #define CAP_ROGUEVIZ 0
 #endif
 
+#ifndef CAP_RVSLIDES
+#define CAP_RVSLIDES (CAP_TOUR && !ISWEB)
+#endif
+
 #ifndef CAP_PROFILING
 #define CAP_PROFILING 0
 #endif
@@ -210,7 +230,7 @@
 #endif
 
 #ifndef CAP_ORIENTATION
-#define CAP_ORIENTATION ISMOBILE
+#define CAP_ORIENTATION (ISMOBILE || ISWEB)
 #endif
 
 #ifndef CAP_MOUSEGRAB