proposal: GitHub-style issue filters #297

Currently, Tangled uses a setup where you have ?state=open or ?state=closed and then also a search string when filtering issues.

I'd like to suggest adding a series of tags (is:, author:, and label:) that would move those filters to the search string.

Examples:

• is:open (all open issues)
• is:closed (all closed issues)
• is:open author:hayden.moe proposal
• is:closed knotserver

I think it'd make filtering issues a fair bit easier.