Merge pull request #190 from tkruse/fix_groovysh_tests

Fix groovysh tests
Make classpath file opening more robust against non-jar files.
Better test output
Fix missing filepath URL decoding on Windows
code style
make tests Preferences-safe
fix test jar url
Merge pull request #191 from tkruse/windows_fix

Fix small bugs due to bad URL decoding
GROOVY-6160: @DelegatesTo should be @Documented
deactivate test which assumes existence of jar under user.dir/lib and fails on the buildserver
also show stacktrace for failed tests of subprojects
only scan jar files for packages to avoid FileNotFoundExceptions with unpackaged classes
GROOVY-6134: Make @DelegatesTo support mapping to a generic argument type
fix tests failing on different JDK due to different Collection ordering
(also removes obsolete comments)