[backport] Chat: Use Ctrl-A for 'select all' again (instead of Ctrl-B)
Backport of 783959a6810b to branch ui-scaling by sheepluva
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.