[TASK] Cleanup

Removes some unneeded/unrelated code and provides some
(partly cosmetic) cleanups:

* Remove HTML cache parts
* Remove unrelated AccountCommandController & HelloControllers
* Adjust IsbnLookupService to fetch book description, too
* Remove "DEFAULT CHARACTER SET utf8" from migrations
* Minor cleanups
[BUGFIX] Redirect to index after creating book via ISBN

Adds a redirect call I removed accidentally.
Also adds some cropping to the book summary in
the overview
Merge pull request #1 from bwaidelich/master

Works great, thanks for taking care.