Add a Not parser;

Add the tests for XAtLeastOnce parser.
Add IgnoreCase parser
Fix the bug in Optional parser that consumes input
if the given parser partially matched.
Merge pull request #14 from winteryoung/master

Add a not parser
adding a bit more visibility into why a parse fails
Merge pull request #16 from davidalpert/richer-debug-info

adding a bit more visibility into why a parse fails
Added Sequence() and Contained() parsers

This makes it a bit easier to implement things like parsing
arrays.
Added some more convenience Char parsers
Added a test for Chars() with string
Merge pull request #19 from rossipedia/chars

Chars
Merge pull request #20 from rossipedia/sequence

Added Sequence() and Contained() parsers
Fix build break. Sprache.csproj file was missing Parse.Sequence.cs