Added a loading flag to the Pica Model to make it easier to handle the
display of loading spinners (though this is too obscue to merge into
pica.js master).
Merge branch 'master' of github.com:unepwcmc/BlueCarbon

* 'master' of github.com:unepwcmc/BlueCarbon:
  improvements on help text markup
  Add text to help section
  ReIntroduce Evidence type for validations
  User should be directed to the validation page when logging in