Lua API: Remove empty functions CampaignLock and CampaignUnlock
Those were just no-op. Better use the issue tracker for suggestions?
Lua scripts for engine testing. These scripts are the same as other Lua scripts
in Hedgewars, but you ought to call `EndLuaTest(TEST_SUCCESSFUL)` or
`EndLuaTest(TEST_FAILED)` when the test is completed.