Implement ArrayConvertible for ContentList paging
Return null if object not ArrayConvertible
Do not convert paging to items list in toArray
Filter out null values, set to null if non-array-convertible-object
Return 'null' on non-array-convertible-object
Remove to/fromArray
Readd CM_ArrayConvertible implementation
Order methods
Do not return early in Params::encpde
Introduce CM_Params::jsonEncode/Decode
Move is_object -> null out of jsonEncode
Merge pull request #1304 from tomaszdurka/issue-1304

BREAKING: Ignore objects in CM_Params::encode