Add Metainfos to User

Adding (required):
- first_name
- last_name
- school_year_begin
- school_year_end

Additional:
- title
- profession
- date_of_birth

Boolean:
- graduated
- was_in_boarding_school
add Guard and RSpec
validate school year range and add inputs for dates
remove most of the optional stuff from the sign up
form
Merge pull request #1 from consti/Feature/AddMetaInfoToUser

Add Metainfos to User