fixes DbUp/DbUp#44

1. Created "SqlCommandReader" class - heavily influenced from an article I read: http://haacked.com/archive/2007/11/04/a-library-for-executing-sql-scripts-with-go-separators-and.aspx/)

2. Unit test passing. Tests a moderately complex sql string that was previously failing with the old splitting logic.

3. I added a nuget package to the unit tests project for the NUnit test adapter for vs2012 / 2013 - this was so i could run the NUnit tests from within VS.. I don't think this should cause anyone any issues but if you would like me to remove that then I can.
fixes DbUp/DbUp#44
Formatting changes as per comments on #50
Tidying for #50 and Fixes #51

1. Refactored SqlCommandReader - removed the spaghetti.
2. Tidied unit test, removed the whitespace etc.
3. Added support for splitting on GO with a terminator (semicolon)
#50 yet more tidying
#50 Even more tweeks and tidy ups.
1. Removed some redundant code.
2. Removed unnecessary usage of 'this'
#50 some more tidying.
Merge remote-tracking branch 'dazinator/master'