Rewrote timeseries detail view
Rewrote instrument detail view; changes also in timeseries detail view
Rewrote view model_add
Removed everything related to django-profiles

django-profiles appears to be an obsolete app. Allegedly much of its
functionality has been included in django-registration, or was never
important. In any case, it can't be used, since it's obsolete.

However, model enhydris.hcore.models.UserProfile still remains. It's not
clear what its function is and whether it also should be removed, and
what kind of migration should be needed for existing installations.
Also removed django-profiles from installation instructions
Removed specialized registration form

django-registration has gone a long way since it was installed in this
projects, and everything related to it will probably need to be
rewritten. We begin by just removing all custom functionality.
Removed custom django-registration urls

django-registration has gone a long way since it was installed in this
projects, and everything related to it will probably need to be
rewritten. We begin by just removing all custom functionality.
Fixed some wrong statements in urls.py
Fixed several errors