gui: Added fine alignment controls. NOTE: Scale window has temporarily been hidden due to layout issues
andorcam2 + andorshrk: share the hardware access

pretty ugly, as it's adding quite a lot of complexity to the already complex acquisition thread
In addition, it's hard to track when the hardware is actually acquiring, and to ensure we only acquire/release once the lock.
So this is actually not supported when the acquisition is synchronised.

Anyway, that should be enough to deal with the one annoying case: during acquisition setup on the SPARC.
andorcam2: add comment on how to clean up code
Merge branch 'master' of vpn.delmic.com:odemis
img: improve mergeMetadata to not correct metadata if it's not present

also fix the default pixel size correction to 1x1 (not 0x0!).

Add a simple test case. More test cases would be welcome.
acq mng: fix typo to really use emission wl for ordering streams

was using exictation wavelength... would probably give mostly the same order, but technically, it's emission that matters.
acq stream: change OverlayStream to make it following the standard interface

the Future of acquire() must return from .result() a DataArray.

also simply the name of the VAs