Allow dashes in tags on travis (#334)

* Allow dashes in tag for Maven travis build
* Allow tags with dashes for the Gradle build

.travis.yml

@@ -17,9 +17,9 @@ jobs:
       env: SBT-JAVA
     - script: sbt publishLocal && cd plugin-tester-scala && sbt compile
       env: SBT-SCALA
-    - script: sbt publishM2 && cd plugin-tester-java && mvn -Dakka.grpc.project.version=`git describe --tags | sed -e "s/v\([0-9]*.[0-9]*\)-\([0-9]*\).*/\\1+\\2-/"``git rev-parse HEAD | head -c8` akka-grpc:generate compile
+    - script: sbt publishM2 && cd plugin-tester-java && mvn -Dakka.grpc.project.version=`git describe --tags | sed -e "s/v\(.*\)-\([0-9][0-9]*\).*/\\1+\\2-/"``git rev-parse HEAD | head -c8` akka-grpc:generate compile
       env: MAVEN-JAVA
-    - script: sbt publishM2 && cd plugin-tester-scala && mvn -Dakka.grpc.project.version=`git describe --tags | sed -e "s/v\([0-9]*.[0-9]*\)-\([0-9]*\).*/\\1+\\2-/"``git rev-parse HEAD | head -c8` akka-grpc:generate scala:compile
+    - script: sbt publishM2 && cd plugin-tester-scala && mvn -Dakka.grpc.project.version=`git describe --tags | sed -e "s/v\(.*\)-\([0-9][0-9]*\).*/\\1+\\2-/"``git rev-parse HEAD | head -c8` akka-grpc:generate scala:compile
       env: MAVEN-SCALA
     - script: sbt publishM2 && cd plugin-tester-java && ./gradlew --include-build ../gradle-plugin clean compileJava
       env: GRADLE-JAVA

gradle-plugin/build.gradle

@@ -21,7 +21,7 @@ group = "com.lightbend.akka.grpc"
 // https://github.com/palantir/gradle-git-version/issues/97
 
 def tag = "git describe --tags".execute().text.substring(1).split("-g")[0].replace("\n", "")
-def finalVersion = (tag == versionDetails().lastTag.substring(1)) ? tag : tag.replace("-", "+") + "-" + versionDetails().gitHash.substring(0, 8)
+def finalVersion = (tag == versionDetails().lastTag.substring(1)) ? tag : tag.reverse().replaceFirst("-", "+").reverse() + "-" + versionDetails().gitHash.substring(0, 8)
 
 version = finalVersion