End user documentation

[annybs]

Although the user interface is - hopefully! - fairly self explanatory and simple to use, it never hurts to actually write about it.

Following the v1.0.0 release it would be helpful to add some sort of end user documentation in addition to the maintainer documentation.

• Creating/logging in to an account
• Creating a herd
• Adding and managing tasks
• Search features
• Deleting data (including account)