Lint whole package for gosimple and gotype

Fixes #936

test/command_callback/test_gosimple_command_callback.vader

@@ -0,0 +1,12 @@
+Before:
+  runtime ale_linters/go/gosimple.vim
+  call ale#test#SetFilename('../go_files/testfile2.go')
+
+After:
+  call ale#linter#Reset()
+
+Execute(The default gosimple command should be correct):
+  AssertEqual 'cd ' . ale#Escape(expand('%:p:h')) . ' && '
+  \ . ' gosimple .',
+  \ ale_linters#go#gosimple#GetCommand(bufnr(''))
+