deposit: empty subject in deposition form

* Adds possibility to set subject to empty in
  deposition form.

* Makes empty subject the default option.

Signed-off-by: Kamil Neczaj <kamil.neczaj@cern.ch>
assets: less flavor of bootstrap

* Removed inspire.css since it is no longer needed
* Added the "less" filter parameter on the LESS
* Fixed Font-Awesome issue after clean installation

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
deposit: icons removed from the labels

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>
global: .gitignore ignores dump.rdb

Signed-off-by: Georgios Kokosioulis <georgios.kokosioulis@cern.ch>