Add a way for the ngo to add activity area

[onel]

From the account the ngo should be able to choose some domain that the ngo is active in, eg: health, education, etc. He may choose more than one from a prepopulated drop down.

This requires front and backend changes.

[danniel]

Deocamdata ma ocup eu de acest issue.

[RaduCStefanescu]

These 2 issues are linked: https://github.com/code4romania/redirectioneaza/issues/43

[tudoramariei]

Closing since issue #43 already covers the work that remains here.