Fix tweaks not being reset for single tests
Fix searching on is_multiple composite fields

Merge branch 'master' of https://github.com/cbhaley/calibre
Fix a regression that broke moving libraries in 1.0

Fixes #1216401 [calibre, version 1.0.0 'function' object has no attribute 'exists_at'](https://bugs.launchpad.net/calibre/+bug/1216401)
newdb: Handle multiple different case items when setting many-many fields

Fixes #1216398 [Same tag twice in different case causes ConstraintError](https://bugs.launchpad.net/calibre/+bug/1216398)
Avoid reading splitter on every call, only read once at startup
Tests for searching on composite fields
Fix sorting for composite cols that are marked as numeric

Incidentally, the implementation of size suffixes in the old db was
broken.
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Sorting for composite cols marked as dates
Composite column bool sorting
Fix sorting for is_multiple custom cols
Sort is_multiple composite columns when displaying them in the book list
Remove unused olddb code paths
Fis reset tweaks in test not applying to field_metadata in Metadata objects
Print out how long each test takes and slowest tests
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newdb: Speed up S&R in the bulk metadata edit dialog
Add a prominent reference to the user manual in the adv search dialog
Retry cleanup to avoid errors due to transient file locks on windows