Removed syntastic and replaced it with ale

Read more here:
https://github.com/w0rp/ale

sources_non_forked/ale/ale_linters/go/gosimple.vim

@@ -0,0 +1,15 @@
+" Author: Ben Reedy <https://github.com/breed808>
+" Description: gosimple for Go files
+
+function! ale_linters#go#gosimple#GetCommand(buffer) abort
+    return ale#path#BufferCdString(a:buffer) . ' gosimple .'
+endfunction
+
+call ale#linter#Define('go', {
+\   'name': 'gosimple',
+\   'executable': 'gosimple',
+\   'command_callback': 'ale_linters#go#gosimple#GetCommand',
+\   'callback': 'ale#handlers#go#Handler',
+\   'output_stream': 'both',
+\   'lint_file': 1,
+\})