Added Lines Before Namespace Fixers

NoBlankLinesBeforeNamespaceFixer is a contrib level fixer, and OneBlankLinesBeforeNamespaceFixer is a symfony level fixer. This also includes some utils refactoring and improvements.
It is not in 1.4 as this PR is not merged yet :) and the method is added in this PR

talking about countLines() now, splitLines() indeed has to wait with renaming, docblock could be changed alreday ofcourse to describe the intention of the method and perhaps mark as @deprecated ?