Better sanity checking for obfuscation feature

Change-Id: I6833ca0b7d06495727a89b9cc83551b995e62199
Signed-off-by: Stormrose <eturnerx@gmail.com>
BUG: blank passage titles and links causing exceptions

Notified by Philip Sutton

Change-Id: Ia8f5e41ef29c7dc3729f9fddce772aca316b1436
Signed-off-by: Stormrose <eturnerx@gmail.com>