json: implement simple ignoring fields comparison
json: add 'isNull' and 'isNotNull' assertions
json: add 'isNumber' assertion
json: add 'isString' assertion
json: add 'isBoolean' assertion
json: add 'isEmptyString' assertion
json: add 'isStringNotEmpty' assertion
json: add 'notContain' assertion
json: add 'notContainOrIsNull' assertion
json: reformat error messages
response: add tests and fix npe on response constructors
cookies: add tests on cookie constructors
json: rename 'isStrictlyEqualToIgnoringField' by 'isEqualToIgnoringField'
json: add contains with a list parameter
Merge branch 'master', remote branch 'bitbucket/master'