Add column to Waffle for the current sprint

[dylanPowers]

@hosh You have the most knowledge on this.

Some column names for the current sprint:

• Sprint
• Ready

For the backlog column:

• Keep the current name?

[jbenet]

👍 for Sprint.

[dylanPowers]

I've added in the sprint column to http://waffle.io/ipfs/ipfs. How do you like it @jbenet? We're starting to get a lot of columns, but I think it's still manageable.

[jbenet]

@dylanPowers that looks good to me! maybe we should make it a habit to go through it every sprint. let's do it next week