Location: only delegate to File.isHidden() on Windows

This bypasses substantial performance problems when calling isHidden()
on Mac OS X/Linux over NFS.  Fixes #6586, see #12027.
FormatReader: speed up getUsedFiles()

We can assume that each call to getSeriesUsedFiles(...) will contain an
array with no duplicates.  If there is only one series in the fileset,
then, we can speed up large filesets by removing the extra check for
duplicate files.

See #12027.
merge dev_5_0 -D org: PR 951 (Fix up Bio-Formats POMs)
merge dev_5_0 -D org: PR 972 (CZI: restrict dimension adjustment)
merge dev_5_0 -D org: PR 984 (Enable SDT plane preloading by default)
merge dev_5_0 -D org: PR 987 (Volocity: parse timestamps from .atsf files)
merge dev_5_0 -D org: PR 989 (ND2: always set the field index to 2)
merge dev_5_0 -D org: PR 993 (Update docs regarding BF and Eclipse (see #12127).)
merge dev_5_0 -D org: PR 997 (Make macro recording work with Exporter (rebased onto dev_5_0))
merge dev_5_0 -D org: PR 998 (Micromanager fixes)
merge dev_5_0 -D org: PR 1000 (Metadata fixes)
merge dev_5_0 -D org: PR 1003 (Large fileset performance improvements)
merge dev_5_0 -D org

Repository: openmicroscopy/bioformats
Excluded PRs:
  # PR 979 melissalinkert 'SVS import and TIFF export fixes' (status: failure)
Already up-to-date.

Merged PRs:
  # PR 951 ctrueden 'Fix up Bio-Formats POMs'
  # PR 972 melissalinkert 'CZI: restrict dimension adjustment'
  # PR 984 melissalinkert 'Enable SDT plane preloading by default'
  # PR 987 melissalinkert 'Volocity: parse timestamps from .atsf files'
  # PR 989 melissalinkert 'ND2: always set the field index to 2'
  # PR 993 bpindelski 'Update docs regarding BF and Eclipse (see #12127).'
  # PR 997 melissalinkert 'Make macro recording work with Exporter (rebased onto dev_5_0)'
  # PR 998 melissalinkert 'Micromanager fixes'
  # PR 1000 melissalinkert 'Metadata fixes'
  # PR 1003 melissalinkert 'Large fileset performance improvements'

Generated by OMERO-5.0-merge-daily#614 (http://ci.openmicroscopy.org/job/OMERO-5.0-merge-daily/614/)