Changed configured Solr fields to use I18n labels

- Added convenience wrapper method on top of BL's config.add_*_field methods
  that simplifies adding I18n labels for the various fields.
- Using convenience wrapper for adding the various fields.
- Added labels for the various fields.
Merge branch 'master' of ssh://github.com/dtulibrary/toshokan

Conflicts:
	config/locales/en.yml
I18n stuff for solr fields.

- Added more I18n labels.
- Added I18n load_path prior to doing BL config in the catalog controller
  since Rails has not yet added its paths to it at the time of config.
Merge remote-tracking branch 'origin/master'