Fix: ReferenceError: assignment to undeclared variable currentExpression
Merge branch pull request 2619

* pr/2619:
  Fix: ReferenceError: assignment to undeclared variable currentExpression
Added the PATCH and HEAD methods
Doc
Typo
Merge: Added the PATCH and HEAD methods to Request

* pr/2610:
  Typo
  Doc
  Added the PATCH and HEAD methods