Proposal: Replace bundled gtest directory with Git submodule

[shymega]

This PR replaces the bundled /ext/gtest directory with a Git submodule locked at the same release as before - 1.6.0 - but it should be considered to bump the release in the near future when and if possible.

Thoughts?

[shymega]

Oh, I can see CI is failing. Probably because the CI scripts don't initialise and pull Git submodules. Will look into it.

[shymega]

OK, that looks like it works with CI now. Thoughts, anyone? CC: @the-wes, @p12tic

[shymega]

Just removed the ext/gmock directory, as the new ext/gtest submodule actually contains both Google Mock and Google Test now. So we'll need to factor that into the testing as well, and possibly consider whenever to keep either/both of them.

[shymega]

Oh, wait, that's a mistake.. v1.6.0 hasn't made that change yet. I messed up there.

OK, will revert that last commit, and add gmock again. Sorry!

[shymega]

OK, made some more mistakes, but should be fixed now. I've locked Google Mocking at v1.6.0.

To give some clarification, Google Testing now has mocking in the same project, and the Google Mock repo is now archived, but the v1.6.0 tag still exists.

I've created another Git submodule for gmock. My previous commits were mistaken, and I had messed it up a bit. Its late at night for me, and I think my code quality is suffering!

[shymega]

Possibly should squash those last few commits into one..

[p12tic]

Possibly should squash those last few commits into one..

Yeah, I really need git rebase master in this case :)

[shymega]

I was just gonna squash and merge with the GitHub UI tbh.

[shymega]

Merging in a sec. Is that alright, @p12tic - we good to go?

[p12tic]

Rebased on latest master. Looking into commits again, not all commits need squashing, as that would remove information.