Parse cut operators
Add cut operators to generated parsers
Improve error reporting by requiring cut operators for failure registration
Added cut operation to optional and one-or-more
Improve error reporting by choosing the first rule that failed, and therefore the innermost
Merge branch 'errors/mizushima'

Conflicts:
	spec/PHPeg/Generator/ToClassVisitorSpec.php
	spec/PHPeg/Grammar/PegFileSpec.php
	src/PHPeg/Generator/ToClassVisitor.php
	src/PHPeg/Grammar/PegFile.peg
	src/PHPeg/Grammar/PegFile.php
Added cut operator to features, and cleaned up a bit
Added error reporting to features and improved it a bit