Refactored importer to single file iteration

In the old version the importer iterated over the import file three times:

1. Blank nodes
2. Concepts and Collections (`:foo rdf:type skos:{Concept|Collection}` triples)
3. Notes, Relations, Labels, …

We (@christophwiemers and I) refactored it to do only one iteration. We achieved it by remembering triples we don't understand jet and trying it again later.
Some more importer optimizations
Not using stupid generated relations anymore
Merge branch 'master' of github.com:innoq/iqvoc into importer
Added a new logger for STDOUT and Rails.logger default
Added time measurement and mode detailed log output
Fixed multi_logger
Disabling indexes in mysql while importing
Add idea to gitignore
bumped binding_of_caller
language translations
Fixed "none" language handling

* There is no `nil` or `" "` magic for labels without language anymore. The new consensus is `"none"`.
Merge pull request #165 from wvk/master

Implement simple RDF-ish triple based write API
Fixed language independent /collection uri
Fixed bugs introduced by "none" language

See @2ed0d043a04e74686cd992f4ea544f5f3163a610
Fixed "translation missing" in ref data

See #161
Merge branch 'master' of github.com:innoq/iqvoc
Merge branch 'master' of github.com:innoq/iqvoc into none_language
Belongs to #160
merged master