Ensure that the safe filter doesn't double encode existing entities.
Merge pull request #4 from jrjohnson/doubleencode-safefilter

Ensure that the safe filter doesn't double encode existing entities.
Allow link targets in SafeHTML filter
Merge pull request #5 from jrjohnson/htmlfiltertarget

Allow link targets in SafeHTML filter
Fix PDF validator mime types

application/octetstream and binary/octetstream are not valid mime types, however they have shown up in logs so we are adding them to be safe.