Add release helper file

Author: tidwall

scripts/RELEASE.md

@@ -0,0 +1,10 @@
+**To bump a new release of Tile38**
+
+- Update CHANGELOG.md to include the newest changes.
+- `git commit -m $vers` changes (where `$vers` is a semver)
+- `git tag $vers`  (where `$vers` is a semver)
+- `git push --tags`
+- `git push` 
+- `make package`
+- Add a new Github Release and add the zips from packages directory.
+