fix #498

Note:

The effect of this fix is that if a metadata field is disabled and an
image is refreshed, that field in the database will be insured to be
NULL.
Make sure the incoming rating isn't higher than what is allowed
Merge pull request #499 from SubJunk/master

Make sure the incoming rating isn't higher than what is allowed
fix typo
fix typo in tab link
#497

This adds cache invalidation for posted comments and changes the place
where the static cache is applied. Cost of the latter on my test system
is a 17% increase in time to load the page when the cache is used.
implement formatting for printImageMetadata
Merge remote-tracking branch 'origin/master' into Static-Cache
Missing change
release id 5e19bab1a7
Fix typo
Dutch translation
Merge pull request #502 from zenphoto/Dutch-translation

Dutch translation
Merge remote-tracking branch 'origin/master' into Static-Cache
Merge remote-tracking branch 'origin/master' into 1.4.6
Merge remote-tracking branch 'origin/Static-Cache' into 1.4.6
fix portable URI handling for multiple images
Merge remote-tracking branch 'origin/master' into 1.4.6
#497

Check if caching is enabled before serving a page from the cache
#497

fix possible race conditions
Fix cachefilename for news categories