Add release scripts and instructions

Author: martijndwars

RELEASE.md

@@ -0,0 +1,41 @@
+# Release process
+
+1. Update version string in `build.gradle` (twice), `README.md` to the final version (i.e. non-SNAPSHOT).
+
+```
+./scripts/version.sh OLD_VERSION NEW_VERSION
+```
+
+2. Commit "Release x.y.z", tag this commit with the new version "x.y.z".
+
+```
+git commit -m "Release NEW_VERSION"
+git tag -a NEW_VERSION
+```
+
+3. [Deploy to OSSRH with Gradle](http://central.sonatype.org/pages/gradle.html):
+
+```
+./gradlew -Prelease uploadArchives
+```
+
+4. [Releasing the Deployment](http://central.sonatype.org/pages/releasing-the-deployment.html):
+
+```
+./gradlew -Prelease closeAndReleaseRepository
+```
+
+5. Increment to next version with -SNAPSHOT suffix
+
+```
+./scripts/version.sh OLD_VERSION NEW_VERSION-SNAPSHOT
+...
+```
+
+6. Create a commit for the new version "Set version to a.b.c-SNAPSHOT"
+
+```
+git add README.md build.gradle
+git commit -m "Set version to NEW_VERSION-SNAPSHOT"
+```
+

scripts/version.sh

@@ -0,0 +1,20 @@
+#/usr/bin/env sh
+set -eu
+
+if [ "$#" -ne 2 ]; then
+  echo "Usage: version.sh OLD_VERSION NEW_VERSION" && exit 1
+fi
+
+OLD_VERSION=$1
+NEW_VERSION=$2
+
+files=(
+  "build.gradle"
+  "README.md"
+)
+
+for file in ${files[@]}; do
+  sed -i '' "s/$OLD_VERSION/$NEW_VERSION/g" $file
+done
+
+