Updated to Bevy 0.11

[werner291]

Hi there!

Just a quick version bump with a couple minor tweaks to make this compatible with Bevy 0.11.

Seems to work fine (tested by running the gallery example).

Some points for review:

• Check migrations.md, that accurate? My PR shouldn't be bringing in any user-visible changes, but I dunno if master had anything going on since 0.5
• bevy_normal_material refers directly to github; the crates.io version was stuck on 0.2 for an unknown reason
• Double-check that the gallery UI renders correctly? Seems to have been a breaking API change there with the top/left. It seems alright, though.