Added Alternation class and PositionAssertion class.
Forgot to uncomment some code.
Added CharacterClass.
Slowly implementing ParseGroup
Merge branch 'master' of https://github.com/markm11/CrapoLibrary
Merge branch 'master' of https://github.com/markm11/CrapoLibrary
Added operator* and other copy constructors.
Updated MemoryStream to use update SharedPtr.
Updated MemoryStream to use update SharedPtr.