This adds the Gradle plugins and configuration to use for Sponge plugins to SpongeGradle together with some more general changes and a merge of Gradle changes from SpongeAPI.
Even though I have moved a few classes around for clarity, these changes are not breaking for current users of SpongeGradle, because it should be usually only referenced by the Gradle plugin ID.
This adds the Gradle plugins and configuration to use for Sponge plugins to SpongeGradle together with some more general changes and a merge of Gradle changes from SpongeAPI.
Even though I have moved a few classes around for clarity, these changes are not breaking for current users of SpongeGradle, because it should be usually only referenced by the Gradle plugin ID.
Fixes #1