Add test cases for ghcmod#detect_module()
Create clean test/output directory before testing
Add test cases for ghcmod#basedir()
Add test cases for ghcmod#build_command()
Respect g:ghcmod_ghc_options
Expand path to full path before adding it to &rtp
Add a test case for ghcmod#info()
Convert location values to integer
Remove "Dummy:0:0:" prefix
Add test cases for ghcmod#make('check') and ghcmod#async_make('check')
Add test cases for ghcmod#make('lint') and ghcmod#async_make('lint')
Test b:ghcmod_ghc_options priority