Add JSHint rules to complement allowing multiple var statements,
https://github.com/nasa/openmct/issues/142#issuecomment-212187972
[Code Style] Require one decl per var
[Code Style] Don't require separate var decls
...but allow them (for compatibility with existing code style)
[Code Style] Allow var decl after start of scope
[Code Style] Enforce codestyle during verify task