remove .lgtm file, since the service has been discontinued
see https://github.com/tldr-pages/tldr/pull/1173#issuecomment-266788990 and https://github.com/lgtmco/lgtm/issues/56 for details
This commit is contained in:
see https://github.com/tldr-pages/tldr/pull/1173#issuecomment-266788990 and https://github.com/lgtmco/lgtm/issues/56 for details