Merge as much code from CC-Tweaked/mc-1.18.x into CC:R as possible.

Hopefully this will make tracking changes and merging future CC: Tweaked
development easier! A lot of this is making whitespace and method
ordering even with Tweaked to bring down the diffs, but it also fast
forwards us to CC:T 1.99.0 features.

config/gitpod/Dockerfile

@@ -0,0 +1,19 @@
+FROM gitpod/workspace-base
+
+USER gitpod
+
+# Install custom tools, runtime, etc. using apt-get
+# For example, the command below would install "bastet" - a command line tetris clone:
+#
+# RUN sudo apt-get -q update && \
+#     sudo apt-get install -yq bastet && \
+#     sudo rm -rf /var/lib/apt/lists/*
+#
+# More information: https://www.gitpod.io/docs/config-docker/
+
+# Install Java 8 and 16
+RUN sudo apt-get -q update && \
+    sudo apt install -yq openjdk-8-jdk openjdk-16-jdk
+
+# This is so that you can use java 8 until such a time as you switch to java 16
+RUN sudo update-java-alternatives --set java-1.16.0-openjdk-amd64