Extended yarn ship: more automation

no issue

- added gulp task to extend casper release automation
- will draft the release for you
- will get the user facing commits from changelog
- runs after `yarn ship` (postship)
- full automation with env variables is possible

package.json

@@ -18,7 +18,8 @@
         "test": "gscan .",
         "pretest": "gulp build",
         "preship": "yarn test",
-        "ship": "STATUS=$(git status --porcelain); echo $STATUS; if [ -z \"$STATUS\" ]; then yarn version && git push --follow-tags; fi"
+        "ship": "STATUS=$(git status --porcelain); echo $STATUS; if [ -z \"$STATUS\" ]; then yarn version && git push --follow-tags; else echo \"Uncomitted changes found.\" && exit 1; fi",
+        "postship": "git fetch && gulp release"
     },
     "author": {
         "name": "Ghost Foundation",
@@ -44,6 +45,7 @@
     "bugs": "https://github.com/TryGhost/Casper/issues",
     "contributors": "https://github.com/TryGhost/Casper/graphs/contributors",
     "devDependencies": {
+        "@tryghost/release-utils": "0.2.0",
         "autoprefixer": "9.4.10",
         "beeper": "1.1.1",
         "cssnano": "4.1.10",