Show path in rlv title bar

[dagewa]

When comparing dials.reciprocal_lattice_viewer windows side by side it could be difficult to keep track of which was which because the title bar just says "Reflection data viewer". This change makes it more similar to the dials.image_viewer, by printing a useful path up there (here the path to reflections)

[dagewa]

Oops looks like I branched off #1770, so included those changes here too

[Anthchirp]

git rebase --onto master 002dc1835e71a5cbe649551c47361798b35d7fd1 && git push -f
should now be the correct set of commits?

[dagewa]

Looks right. Thanks for untangling.

[ndevenish]

The test failures on previous commit are because it looks like the feature branch was inadvertantly rebased onto master instead of main. Merged in again.

[Anthchirp]

rebased onto master instead of main

🤦 sorry

[ndevenish]

It's hard to train out that muscle memory sometimes :)