Check all parts of a  concatenated echo statement, ignore function arguments within echo statements.
Relates to #33
Extend XSS check to _xx functions family
Closes #33
Fix unit test php short tag, causing Travis to fail.
Add test for nested functions inside of escaping function
Fix detection of closing parenthesis of functions
Use addError native string formatting.
Resolve develop branch conflicts w/ EscapeOutputSniff

Merge branch 'develop' into issue/33

Conflicts:
	Tests/XSS/EscapeOutputUnitTest.inc
Merge pull request #95 from WordPress-Coding-Standards/issue/33

Improve XSS Sniff