In syntax 1.0 the groovy parser doesn't support xcontext. Also context and xcontext should be the same api.Context object

#1 The bug: In syntax 1.0 the Context is known only as 'context' and not as 'xcontext'. Since 'xcontext' is the new standard, it should be back ported to groovy.

#2 The Improvement: In syntax 1.0 velocity (and groovy since revision 26046) xcontext and context are different api.Context objects although they point to the same underlying XWikiContext object.