Add http PATCH method support to rest controllers.

When issuing a PATCH request a resource should be "patched", that is updated only with the properties submitted maintaining the rest of its properties. In contrast to POST requests, the later update the whole resource regardless of any data already there.
introduce a failing test

This failing test demonstrates one of the things that is wrong with the code currently included in the PR at https://github.com/grails/grails-core/pull/495.
correctly propagate isInteractive system property
calculate interactive system property independently of GrailsConsole
initial cut of grails-dependencies subproject for generating the pom.xml from GrailsCoreDependencies
fix Spring version
add more the generated POM, delete non-generated version
add signing of the POM
2.4.1.BUILD-SNAPSHOT
add deployment of snapshots and releases using maven-ant-tasks
disable Gradle signing, since handled by Maven
Merge branch 'master' of github.com:cesarizu/grails-core into cesarizu-master

Conflicts:
	grails-web-url-mappings/src/main/groovy/org/codehaus/groovy/grails/web/mapping/DefaultUrlMappingEvaluator.java
Merge branch 'cesarizu-master' into 2.4.x
Merge branch '2.4.x' of github.com:grails/grails-core into 2.4.x
use 2.4.0 maven plugin
Merge branch 'grails-dependencies' into 2.4.x
fix inter task dependencies
reinstate signing plugin, looks like it was needed
GRAILS-11434 missing quotes in startGrails.bat
GRAILS-11430 fix NPE when reloading the same scaffolded page several times