Adds gradle tasks to build all plugin scripts under data/plugins with
the KotlinPluginCompiler implementation previously used for runtime code
generation. In addition to .plugin.kts files, scripts can also declare
API code in .kt files which will also be included on the classpath and
made available to other plugins.
Creates a new sourceset for server plugins to support IDE integration
with plugin code. Additionally moves plugins to game/data/plugins and
contains some gradle related fixes (remove java plugin from root project
and fix exec task dependency).
Ports the Maven build POMs to Gradle build scripts, which are a bit
friendlier to use. Instead of using the exec:java Maven goal to run the
server now, the gradle run task should be used.
Gary Tierney