Only show bullet hits for shovable gears
Fixes some weird bullet hit vgears spawning when hitting non-shovable gears like snowflakes
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.