added some PEG tests
added match base class
added tests for Matcher
StringMatcher, match function and other match improvements
added grammar_factory
Merge branch 'master' into peg
Merge branch 'master' into match
renamed StringGrammarDefinition -> String
added RegularExpressionMatcher
fixes WeightedParser test errors
improved README
Merge branch 'master' into peg
added test for Choice
adds comment
removed Choice as is equivalent to AlphabetListDefinition
improved documentation #57
fixed broken tests
Merge branch 'master' into peg
Alphabets are now GrammarDefinitions
removed Definition from GrammarDefiniton and AlphabetDefinition