Add support for AWS file storage with Dragonfly ...

Fixes #1976

Commented out deprecated user.organisation_id method (#29) ...

* updated dragonfly max logo height/width to 160px to fit with current max size of DMPRoadmap logo

* updated organisation edit page's error messages so that errors are placed in the alert text section. Updated wording in locale files to reflect the 160x160 file size.

* removed height and width constraints to logo upload function. Added method that will resize the uploaded logo so that the width is 160px (maintaining aspect ratio) so that the logo fits within the layout properly

* changed logo size to a height of 100 and moved logo so that it appears alongside the DMPRoadmap logo per the current specifications

* Removed description field from organisation. Add contact email to the organisation. Change the way the logo is displayed on the organisation screen.

* commented out legacy user.organisation_id method in user model. Each user now belongs to one organisation

Merging current stable development branch into master (#23) ...

This is our unofficial v.0.1.0 release. It includes:
- Rails 4.2 migration
- Internationalization
- API
- Institutional logo upload (thanks to Weiwei and the Univ. of Alberta)
- Generic branding
- General cleanup of code and bug fixes