Fixes for setTags() and empty tags

FIX: setTags() did not call loadTags(). Furtheron, neededSave() would
re-save even though no tags had changed, or not save when empty
setTags(array()) was called.

FIX: in for loop while saving in afterSave(), when empty tag was found,
continue instead of aborting.

CHG: remove empty tags before handling
ADD: pass additional parameter to taggedWith() which allows matching ANY
tag instead of ALL tags
FIX: when tag tables are not set, automatically remove and add prefix {{
}}
Revert "Fixes for setTags() and empty tags"

This reverts commit ce0414a547ddd9ab97ad8bde717d3e7bc5505551.
Revert "ADD: pass additional parameter to taggedWith() which allows matching ANY"

This reverts commit e06b34f576e2eb8d7c867bd7c7828736acee0ad0.
update changelog
Merge pull request #22 from marcovtwout/tableNames-stripPrefix

FIX: when tag tables are not set, automatically remove and add prefix {{ }}