- always store media references in fields in NFC form
- always encode filenames on disk in NFC form on machines other than macs
- use relevant encoding when placing files in the media folder during syncs
and apkg imports as well
- rename 'unused media' back to 'check media'
- check media can now automatically change media references and filename
encodings to the correct format
- add writeData() so we can add files to media folder without having to
save them in an intermediate folder first
- we were stripping or checking for illegal filename characters in
multiple places; factor those checks out into separate routines
- add * to invalid char list, and disallow both forward and backslash
- remove size checks in syncAdd(); is handled server-side
- split quoted and unquoted image case into separate regexps, since we can't
include a group reference inside a character set
- disallow spaces in the non-quoted case
- this should fix matching on images with other attributes again
