Add release script

Currently the Tycho release requires some preliminary steps, waiting for
some things to appear and also fill out some templates that basically
need:
- the current release version
- the next release version
- the previous release version

all these tasks are cumbersome and error prone, so this adds a shell
script that calculates the versions and check for the urls to be present
and giving the required template already filled out.

release.sh

@@ -0,0 +1,93 @@
+#!/bin/bash -e
+function usage
+{
+        echo "Please provide PGP key email"
+        exit
+}
+
+[ "$#" -eq 1 ] || usage
+
+CURRENT_SNAPSHOT_VERSION=$(mvn help:evaluate -Dexpression=project.version -q -DforceStdout)
+RELEASE_VERSION=${CURRENT_SNAPSHOT_VERSION%-*}
+echo "Performing Release $RELEASE_VERSION"
+RELEASE_MAJOR=$(echo ${RELEASE_VERSION} | cut -d'.' -f1)
+RELEASE_MINOR=$(echo ${RELEASE_VERSION} | cut -d'.' -f2)
+RELEASE_MICRO=$(echo ${RELEASE_VERSION}| cut -d'.' -f3)
+NEXT_RELEASE_MICRO=$((RELEASE_MICRO+1))
+PREV_RELEASE_MICRO=$((RELEASE_MICRO-1))
+
+PREV_RELEASE_VERSION=${RELEASE_MAJOR}'.'${RELEASE_MINOR}'.'${PREV_RELEASE_MICRO}
+NEXT_RELEASE_VERSION=${RELEASE_MAJOR}'.'${RELEASE_MINOR}'.'${NEXT_RELEASE_MICRO}
+
+waitforurl() {
+  while [ $(curl -s -o /dev/null --head -w "%{http_code}" ${1}) -ne "200" ]; do
+    printf '.'
+    sleep 5
+  done
+  echo " Release record found!"
+}
+
+echo "Plase create a release record here:"
+echo "- https://projects.eclipse.org/node/1631/create-release"
+waitforurl https://projects.eclipse.org/projects/technology.tycho/releases/${RELEASE_VERSION}
+git pull
+git fetch --all --tags
+mvn versions:set -DnewVersion=${RELEASE_VERSION}
+sed -i -e "s|<version>${CURRENT_SNAPSHOT_VERSION}</version>|<version>${RELEASE_VERSION}</version>|g" tycho-extras/tycho-eclipserun-plugin/pom.xml
+git add -u
+git commit -m "Perform ${RELEASE_VERSION} release"
+mvn clean deploy -Prelease -DskipTests \
+     -DforgeReleaseId=sonatype-nexus-staging \
+     -DforgeReleaseUrl=https://oss.sonatype.org/service/local/staging/deploy/maven2/ \
+     -Dgpg.keyname=$1 \
+     -Dmaven.repo.local=/tmp/tycho-release
+mvn install site site:stage -DskipTests -Dmaven.repo.local=/tmp/tycho-release
+TYCHO_DIR=$(pwd)
+pushd -n ${TYCHO_DIR}
+cd ..
+cd eclipse-tycho.github.io
+git pull
+cd doc
+sed -i "11 a <li><a href='${RELEASE_VERSION}/index.html'>${RELEASE_VERSION}</a></li>" index.html
+cp -r ${TYCHO_DIR}/target/staging ${RELEASE_VERSION}
+rm latest
+ln -s ${RELEASE_VERSION} latest
+cd ..
+git add -u
+git add doc/${RELEASE_VERSION}
+git commit -m "Add documentation for ${RELEASE_VERSION} release"
+popd
+git tag tycho-${RELEASE_VERSION}
+mvn versions:set -DnewVersion=${NEXT_RELEASE_VERSION}-SNAPSHOT
+sed -i -e "s|<version>${RELEASE_VERSION}</version>|<version>${NEXT_RELEASE_VERSION}-SNAPSHOT</version>|g" tycho-extras/tycho-eclipserun-plugin/pom.xml
+git add -u
+git commit -m "Prepare for ${NEXT_RELEASE_VERSION} release"
+echo "Everything is prepared now, please review the release, the prepared docs and updated versions and close the staging repository:"
+echo "- https://oss.sonatype.org/#stagingRepositories"
+echo "After that, when all checks passed also release it!"
+echo "Now wait until release became visible on maven central..."
+waitforurl https://repo1.maven.org/maven2/org/eclipse/tycho/tycho-core/${RELEASE_VERSION}/tycho-core-${RELEASE_VERSION}.jar
+echo "You should now push the branch and the documentation after that create the release record for Github here:"
+echo "- https://github.com/eclipse-tycho/tycho/releases/new"
+echo ""
+echo "Subject: Tycho ${RELEASE_VERSION} is released"
+echo ""
+echo "Tycho ${RELEASE_VERSION} has been released and is available from Maven Central repository."
+echo ""
+echo "🆕 https://github.com/eclipse-tycho/tycho/blob/tycho-${RELEASE_VERSION}/RELEASE_NOTES.md"
+echo "🏷️ https://github.com/eclipse-tycho/tycho/tree/tycho-${RELEASE_VERSION}"
+echo "👔 https://projects.eclipse.org/projects/technology.tycho/releases/${RELEASE_VERSION}"
+echo "🙏 contributors who contributed patches for this release:"
+git log --pretty=format:%an tycho-${PREV_RELEASE_VERSION}..tycho-${RELEASE_VERSION} | sort | uniq
+git log --grep="Also-[bB]y:" tycho-${PREV_RELEASE_VERSION}..tycho-${RELEASE_VERSION} | grep -i also-by | sed -e 's/.*Also-[bB]y:\s*\(.*\)/\1/' | sort | uniq
+echo "💰 we would like to also thank <list of sponsors> for sponsoring contributions in this release"
+echo ""
+echo "and thanks to everyone who helped us with testing the snapshot version."
+echo ""
+echo "Regards,"
+echo ""
+echo " The Tycho Team"
+echo ""
+waitforurl https://github.com/eclipse-tycho/tycho/releases/tag/tycho-${RELEASE_VERSION}
+echo "Now please send a note to the dev mailing list"
+echo "- [email protected]"