Image library initial implementation

*Moves the BufferedImage loader into the library, rather than being
a loader implemented in common/implementation

common/addons/library-image/src/main/resources/terra.addon.yml

@@ -0,0 +1,12 @@
+schema-version: 1
+contributors:
+  - Terra contributors
+id: library-image
+version: @VERSION@
+entrypoints:
+  - "com.dfsek.terra.addons.image.ImageLibraryAddon"
+website:
+  issues: https://github.com/PolyhedralDev/Terra/issues
+  source: https://github.com/PolyhedralDev/Terra
+  docs: https://terra.polydev.org
+license: MIT License