GROOVY-5839: add test case to avoid regression
Add a cobertura task
GROOVY-5873: generalize generics application and extend to be used on fields
Tried to make the test more robust on the buildserver and to speed it up for faster machines.
Document limitation of normal map-style constructor use when using the Immutable annotation.

See http://groovy.329449.n5.nabble.com/Unexpected-behaviour-when-using-Immutable-on-a-class-with-java-util-Map-field-tp5716170.html
Merge pull request #219 from jwagenleitner/immutable-javadoc

Document limitation of normal map-style constructor use when using the Immutable annotation
Added missing "." at the end of new javadoc for GROOVY-6269.
GROOVY-5883 + GROOVY-6270: ensure the result of a Closure#call is cast to the target type before boolean conversion plus regression test for both
GROOVY-5885: add regression test
GROOVY-6272: Cannot define a no-args closure in Groovy Shell
GROOVY-6272: Cannot define a no-args closure in Groovy Shell

Implemented the improvements suggested by Jason
GROOVY-5069: AstBuilderFromSpecificationTest.testElvisOperatorExpression(): DSL and expected AST incorrect

Applied patch provided by Masato Nagai