Fix syntax errors, doc typos and indentations glitches
Add local error base class 'SmachError', extending Exception
Remove superfluous parent class declaration 'UserData' from 'Remapper'
Add explanations within message definitions
Remove old methods set_userdata
Fix get_internal_edges returning list of tuples, not list of lists
Merge pull request #27 from felix-kolbe/groovy-devel

Syntax errors, documentation improvements, Exception base class and more