Fixes #14476 - Correctly handle casting of invalid real param values

(cherry picked from commit b953c6ae5390adb93e44c6778017373795c9bc63)

Fixes #14129 - remove duplicate declaration of KEY_DELM

(cherry picked from commit 2e1dc83df509910f36753330b26fc74f7e59d2d5)

Fixes #11618 - Replace validation tests by shoulda-matchers

A good chunk of our unit tests are testing whether a validation is
working or not by testing it actively. For the validations we've
added ourselves I would say it's fine. However for validations that...

fixes #11862 - validating that casted hash is valid

Catch parse errors correctly under Ruby 1.9.3, and ensure the uncasted
value is displayed back in the UI if it fails to parse.

Fixes #12343 - Fixing parameters caster for boolean values

Fixes #12078 - list validator in smart class parameters validates any string coercible value

fixes #10232 - moving validations and casting out of lookup key and value