Sniff Improvements

1. NamingConventions.ValidInterfaceName
- code simplified
- cases when interface name start with "I" by itself now taken care of
- sniff renamed from "NamingConventions.InterfacePrefix"
2. Array.Array
- method "sniffItemClosings" was inlined into "process"
3. Classes.ClassCreateInstance
- code updated to fix reported CS violations
4. Classes.ClassDeclaration
- added support for Traits
- namespace presence check moved to new "Classes.ClassNamespace" sniff
- don't allow comments after closing class brace
5. Classes.ClassNamespace
- added
6. Classes.PropertyDeclaration
- private class property name wasn't checked for required leading "_"
7. Commenting.FunctionComment
- fixed detection of functions, that don't have PHPDOC
8. Commenting.InlineComment
- check for inline docblock comments restored, but with exception for "@var" inline comments
9. ControlStructures.ControlSignature
- JS tokenizer added
- removed commented-out code
10. Files.OneTraitPerFile
- added
11. Formatting.BlankLineBeforeReturn
- complete rewrite
- allows preceding inline comment before "return" statement
- checks that there is only 1 blank line before "return" (accounting for preceding inline comment) and reports (0 blank lines or more then 1 blank line are considered as error)
12. Formatting.ItemAssignment
- removed "sniffItemClosings" method (was copy/paste from "Array.Array" anyway)
- "sniffElementItemAssignmentOperator" method inlined into "process"
- now verifies that only spaces (not tabs) are used around "=>" operator
13. Formatting.SpaceOperator
- no longer listens for "equalityTokens" because that caused error to be reported twice because of they are already present in the "comparisonTokens" array
14. Formatting.SpaceUnaryOperator
- code updated to fix reported CS violations
15. Functions.FunctionDeclaration
- returned part of code from parent sniff to check for correct multi-line declaration indentation
16. NamingConventions.ValidFunctionName
- fixed incorrect indentation in code
17. NamingConventions.ValidTraitName
- added
18. Strings.ConcatenationSpacing
- complete rewrite of error message to be more useful
19. WhiteSpace.ControlStructureSpacing
- spaces with do-while construct condition wasn't checked
- error messages changed to include control structure token (e.g. "if", "while", etc.)
- error messages changed to include actual VS expected empty line (for scope) or space (for condition) count
- empty control structures reported 2 errors instead of 1
- empty lines within between "case/default" and "break" weren't checked
- preceding/trailing inline comment of a control structure was reported as an empty line
- if/elseif/else were requiring empty line before after in some cases
Removing DEV dependency for PHPUnit
Fixes for "constants.php" file that can have multiple classes inside

Also use more generic sniffs, that were excluded before
Adding tests