Enabled caching in configuration

This is done for two reasons:

1. Not using caching pollutes the logs.
2. Query-Caching < Caching. Even when AR caches the Querys the results have to be parsed and objectified.
fixed instance configuration caching

* moved condition into caller
* used  as  is initialized as empty hash
fixed typo in routing

no idea what that's there for in the first place though

cf. e88e273786372f9ce54cc47578c50f770e952bbc
Merge branch 'fix_for_140'
whitespace cleanup
replaced Ruby 1.9.2 with 2.0 in Travis CI configuration
Revert "replaced Ruby 1.9.2 with 2.0 in Travis CI configuration"

this was a bit premature:
https://travis-ci.org/innoq/iqvoc/jobs/5158580

I forgot we need to wait for Rails 3.2.13

This reverts commit 93b9923e4d86f34e943a4352777f4317645f305c.
Merge remote-tracking branch 'upstream/master'
Merge branch 'master' into fix_for_140
Belongs to #140 add test for expired concpets.