Add LGTM to readme

[terriko]

[Molkree]

Is this issue about adding LGTM.com badges to the Readme or something else? If it is about badges, would you want number of alerts, code quality or both? Here's how they look for anyone interested:

[terriko]

Yes, this is about adding LGTM.com badges to README.md, to go alongside our other badges.

We were particularly talking about the code quality one in the meeting where I filed this issue, but if the alerts look useful too I don't mind having both. We'll eventually want to have a discussion about streamlining which code quality tools we use, but I think the overhead of adding a couple of badges isn't unreasonable to do to see if we find this one useful.

[XDRAGON2002]

I would like to work on this.

[XDRAGON2002]

Opened PR #1501 that closes this issue.