Message after uploading image. Do not redirect after plugin form submit as changes to article text and title are lost.

Conflicts:
	wiki/conf/settings.py

Corrected parameters on render_to_response. Also fixed login url resolution when ACCOUNT_HANDLING=False.

Deletion for articles: Soft delete and purge. Also soft deletes or purges children. A soft deletion creates a new revision in which the article is marked as deleted.

Do not delete old notifications when user unsubscribes + allow notifications to be created without a subscription (to enable notifications for only one specific user)

Updated install instructions on README.

Pip requirements