Update MockHttpRequestSpec.scala

Added test for parameters with empty values
Update MockHttpServletRequest.scala

Add case matching a parameter with no/empty value ("a=" or just "a")
Added my name and email
Corrected formatting
Update MockHttpServletRequest.scala
Update MockHttpRequestSpec.scala
Fix expectation for blank parameter URI serialization.

Also clarify variable names.
Remove expected IllegalArgumentException for blank parameter in spec.
Merge branch 'issue-1516'

Fix for problem in mock requests where a parameter in the URL has a blank value
(either "a=" or just "a").