Align .gitignore to the one used by Spring 3.4.0 (#416)

* chore: aligned .gitignore to the one used by Spring 3.4.0-SNAPSHOT

* chore: Restored some cases covered by the current .gitignore

grails-forge-core/src/main/java/org/grails/forge/feature/build/gitignore.rocker.raw

@@ -1,14 +1,42 @@
-Thumbs.db
-.DS_Store
+### Gradle ###
 .gradle
 build/
-target/
-out/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
 .idea
+*.iws
 *.iml
 *.ipr
-*.iws
-.project
-.settings
-.classpath
-.factorypath
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Other ###
+Thumbs.db
+.DS_Store
+target/