Increase expectedIndent from +1 to +4 in FunctionCallSignatureSniff

Props @gsherwood
Merge pull request #271 from WordPress-Coding-Standards/feature/issue-270

Increase expectedIndent from +1 to +4 in FunctionCallSignatureSniff
Merge branch 'develop' into feature/upstream-function-call-signature-sniff

Conflicts:
	WordPress/Sniffs/Functions/FunctionCallSignatureSniff.php
	WordPress/Tests/Functions/FunctionCallSignatureUnitTest.inc