Remove Qt SVG and Qt OpenGL as hard dependencies
Qt SVG is not used in the frontend (no SVGs are rendered).
Neither is Qt OpenGL used. Qt OpenGL is discouraged anyway.
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.