added toString() method for CaseInsensitiveHeaders
added unit test for the class

Signed-off-by: Alex <alexlehm@gmail.com>
added toString() method for CaseInsensitiveHeaders (copied from 2.x branch)
added unit test for the class (cleaned up unit tests and fixed checkstyle errors)

Signed-off-by: Alex <alexlehm@gmail.com>
Improve exception for illegal types for Json

Signed-off-by: nscavell <nick.scavelli@gmail.com>
Merge pull request #962 from vietj/master

Remove surefire snapshot
Fix configuration of Starter with options
Fixed configuring of Starter with system properties
Merge pull request #949 from nscavell/master

Improve exception for illegal types for Json
Merge pull request #940 from alexlehm/bz430965

added toString() method for CaseInsensitiveHeaders