[Fix] Mitigate XSS attack vector by cleaning input before it hits our Database (#171)

## Changes

- All text input fields are now cleaned with nh3 to remove html tags. We allow certain html tags under `settings.py/ALLOWED_HTML_TAGS` so we can easily update the tags we allow in the future.
- All names and descriptions now use the template tag `nh_safe` in all html files.
- Usernames and emails are a small exception and are not allowed any html tags

Co-authored-by: Liam Brydon <62733830+MyCreativityOutlet@users.noreply.github.com>
Co-authored-by: jebus <lorsbach@envipath.com>
Co-authored-by: Tim Lorsbach <tim@lorsba.ch>
Reviewed-on: enviPath/enviPy#171
Reviewed-by: jebus <lorsbach@envipath.com>
Co-authored-by: liambrydon <lbry121@aucklanduni.ac.nz>
Co-committed-by: liambrydon <lbry121@aucklanduni.ac.nz>

templates/modals/predict_modal.html

@@ -56,7 +56,7 @@
                         <option disabled>Select a Setting</option>
                         {% for s in meta.available_settings %}
                             <option value="{{ s.url }}"{% if s.id == meta.user.default_setting.id %}selected{% endif %}>
-                                {{ s.name }}{% if s.id == meta.user.default_setting.id %} <i>(User default)</i>{% endif %}
+                                {{ s.name|safe }}{% if s.id == meta.user.default_setting.id %} <i>(User default)</i>{% endif %}
                             </option>
                         {% endfor %}
                     </select>