ND2: only adjust for {Frame,Time}{Before,After} if LoopSize is used

Fixes #11997.
ND2: do not skip bytes at the end of text info blocks

Fixes #11873.
FakeReader: detect multi-file screens from any of the field files

Prior to this, multi-file screens could only be detected from the
top-level directory.  This meant that importing into OMERO would not
have the desired effect, as ImportCandidates automatically recurses into
the directory and picks up the individual field files.

Fixes #12430.
mkfake: prevent the top-level directory name from being just ".fake"

See #12430.  It's a little weird to have e.g. 'mkfake ~/' create
~/.fake/, and makes it a little more difficult to find or remove the
screen directory.  'mkfake ~/' with this change will now create
~/screen.fake/, or ~/screenX.fake/ where X is the smallest index (from
1) for which a directory does not exist.
FakeReader: allow each channel's color to be specified separately

The 'color_x' keys (where x is the channel index) now set the color for
the specified channel.  These keys can be used with 'color', which acts
as a default value for any missing or invalid 'color_x' values.

Fixes #12423.
DICOM: correct units for physical sizes

Fixes #12307.
Fix used file listing for multi-file screens
Add HCS domain when fake image is SPW.
Leica LIF: do not set Channel.Color for RGB images

The stored color will usually (always?) be 0xffffffff, which causes the
displayed colors to be inaccurate (since the 'R' component will be shown
as white).

Fixes #12214.
OME-TIFF: close helper readers when working with single-plane files

The reader will be left open if only a tile was read, but if the full
plane from a single plane file is read then the helper reader will be
closed.  This reduces the memory usage for datasets that consist of many
single plane files.

Fixes #12219.
Change file closing check to look for lower-right-most tile
Merge pull request #16 from bpindelski/add-domains

Add HCS domain when fake image is SPW.
Do not create empty Channel objects
Merge pull request #1178 from melissalinkert/rebased/develop/nd2-part-2

Nikon .nd2 fixes, part 2 (rebased onto develop)
Merge pull request #1195 from melissalinkert/rebased/develop/12219

OME-TIFF: close helper readers when working with single-plane files (rebased onto develop)
Merge pull request #1192 from melissalinkert/12307

DICOM: fix units for physical sizes
Merge pull request #1193 from melissalinkert/12214

Leica LIF: do not set Channel.Color for RGB images
ND2: ignore invalid image offsets

Fixes QA 7534, #11305.
ND2: rework text annotation parsing so that dimensions are not overlooked

Fixes #12205.
ND2: set SizeT to the number of offsets if there is no dimension metadata

See #10773.