Create DEPLOY.md

DEPLOY.md

+# Deployment of new UFrameIT Releases
+
+TODO: describe how to deploy here
+
+## Versioning
+
+Always release [UFrameIT/UFrameIT](https://github.com/UFrameIT/UFrameIT) (this repo) and [FrameIT/frameworld](https://gl.mathhub.info/FrameIT/frameworld) (the MMT archive)
+at the same time with the *same* version number.
+
+Concretely:
+
+1. Create a new GitHub release here: <https://github.com/UFrameIT/UFrameIT/releases>
+2. Merge [FrameIT/frameworld](https://gl.mathhub.info/FrameIT/frameworld)'s devel branch into master and git-tag it appropriately.
+3. Write a news post on our website: <https://github.com/UFrameIT/UFrameIT.github.io>