Merge pull request #119 from mvexel/develop

adding unassign script and small sidebar tweaks
refactoring and adding console statements for debugging task error
remove newline
More debugging
typo
When a user select a new challenge, they also need a new task
Adding iD url and making josm edit work even if there's no selected object
Dumb typo
Replacing edit button with iD button
Fixing get challenge function
Merge branch 'develop' of github.com:osmlab/maproulette into develop

* 'develop' of github.com:osmlab/maproulette:
  Fixing get challenge function
  Replacing edit button with iD button
  Dumb typo
  Adding iD url and making josm edit work even if there's no selected object
  When a user select a new challenge, they also need a new task
  typo
  More debugging
  refactoring and adding console statements for debugging task error
adding slug to default challenge marshal fields
standardizing javascript

proposals for code style conventions at
https://github.com/osmlab/maproulette/wiki/Code-style-conventions
standardizing python code for 2 example files

proposals for code style conventions at
https://github.com/osmlab/maproulette/wiki/Code-style-conventions