* Add tests for conditional mana usage with soft counterspells
* Fix "to cast" conditions on common ManaCondition classes
* Add fix to all remaining ManaCondition classes
* SimpleActivatedAbilityConditionalMana is tested to pay for a soft counterspell activated ability
* Remove now-unused imports
* apply regex to change public copy constructors to protected
* cleanup code using now protected constructors
* fix manaBuilder weird casting of Mana into ConditionalMana
* replaced blocking/blocked by predicates
* added test for knight of dusk (currently fails)
* added source parameter to filters and everything else that needs it
* some changes to various predicates
* test fix
* small changes to filter code
* merge fix
* fixed a test failure
* small change to Karn, Scion of Urza
* removed sourceId from filter methods and other similar places
* added new getobject method to fix some test failures
* a few more fixes
* fixed merge conflicts
* merge fix
* Pay X abilities - fixed that it spends all available mana pool instead only needed;
* Pay X abilities - added support of interactions with other X effects like Rosheen Meanderer's mana usage for "pay X to prevent";
* Rosheen Meanderer - fixed that it can't use mana for "you may pay X" like Flameblast Dragon's effect (#5206);
* Devs: added support to use VariableManaCost to pay X in code (without generic's workaround, use ManaUtil.createManaCost to generate cost to pay);
