Avoid ever creating .deps directory
test1.in is not a test and it must be run always

test1.in generates files like small.vim, tiny.vim, mbyte.vim, mzscheme.vim,
lua.vim which are then used by other tests. So it must be run always.
Allow passing SCRIPTS and TESTNUM arguments when doing `make test`

This will readd a warning current solution is avoiding. I think that warning is
far better then ignoring arguments.