Consistently rename "team chat" to "clan chat" (except chat command) Only change in strings, no functional change. "Team" and "clan" have defined meanings in HW, but "team chat" oddly broke this convention. This feature allows chat with your clan, not with your team, so is now called "clan chat". /team command unchanged to avoid disruption (for now).

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.