Usability improvements

Empty or whitespace-only lines will be ignored
Additional whitespace between event parameters will be ignored
Fold should return IEnumerable, not IReadOnlyList
Rename GetLines->GetMarkdownLines
A simple implementation of the main program
Reuse code between tests
Separate Fold from GetMarkdownLines
Fixed Test3
Make Test3 pass
GIVEN there is no container with id 'x', WHEN i attempt to create a node with parent id 'x', THEN an exception is thrown
Make Test4 pass
Turned on Option Strict and warnings as errors
Bad first implementation of block quotes
Restructured project folder for organisation
Added a C# string parser
Replace C# escapes in block quotes
Refactoring to improve StringParser's interface
Added unit tests for linebreaks in block quotes
StringParser shouldn't stop after one character
Passed linebreak tests
Oops, I meant code block, not block quote