Remove unit types commits and settings (#2161)

* Remove unit types commits and settings

* Can not limit units in administrator teams

* Limit changing units only to teams with read and write access mode

* Small code optimization

options/locale/locale_en-US.ini

@@ -251,6 +251,7 @@ username_been_taken = Username already taken.
 repo_name_been_taken = Repository name already used.
 org_name_been_taken = Organization name already taken.
 team_name_been_taken = Team name already taken.
+team_no_units_error = Team must have at least one unit enabled.
 email_been_used = Email already used.
 openid_been_used = OpenID address '%s' already used.
 username_password_incorrect = Incorrect username or password.