Class renaming and syntax changes to shrink delta with upstream mirclient QPA plugin (which is equivalent to rev 360)
Changes:
- Rename classes to prefix "QMirClient" instead of "Ubuntu"
- Update licence headers to match Qt's
- change logging categories spec to match Qt: qt.qpa.mirclient
- Enforce American English
- some minor syntax tweaks
Some differences still exist:
- QPA plugin remains "ubuntumirclient" and not "mirclient" as used upstream.
- some header paths differ between in-Qt code and externally built code
- I've not included build-type switches for things like accessibility support
- relaxed switch cases to allow older versions of Mir not break a build
- panel height hack removed from upstream
- platform-api env var setting removed from upstream