added spec to make sure that Groovy's @NotYetImplemented works with Spock (addresses issue 124)
remove spec body to work around known groovy 1.8 problem
fixed regression introduced by fix for issue 307 (see discussion in issue tracker)

- also renamed getGeneric... to getExact...
Merge branch 'groovy-1.8' into groovy-1.9

Conflicts:
	spock-specs/src/test/groovy/org/spockframework/smoke/groovy/UsageOfNotYetImplemented.groovy