Should be consistent about "Release" vs. "Sprint"

[njx]

We've started referring to the Brackets releases as "Releases", but some of our stuff still refers to Sprints - e.g. update notifications, release notes. We should figure out what else needs to be cleaned up to make this all consistent.

[njx]

Low pri, randomly assigning to @ingorichter :) (partly because I think some of the other remaining instances are in the build system).

[pthiess]

@ingorichter @njx - marking this a 1.0 as we should come up with release numbers too. I think we want to be consistent and with the switch to Kanban we started to call our sprint releases just Release X.

[ingorichter]

+1 Yes, it makes sense to move towards Release X. I'm always on the fence how to name the Release when I'm posting to G+ and FB.

[ingorichter]

This is the story on the trello board

[redmunds]

In Progress:
#8680
adobe/brackets-shell#462