build: enable sbt-git plugin

This allows reading artefact version number from
the git tag on CI in release profile instead of
hard-coding it in VCS.

Signed-off-by: Alexander Bezzubov <bzz@apache.org>

Author: bzz

build.sbt

@@ -2,7 +2,9 @@
 
 name := "bblfsh-client"
 organization := "org.bblfsh"
-version := "2.0.0-SNAPSHOT"
+
+git.useGitDescribe := true
+enablePlugins(GitVersioning)
 
 scalaVersion := "2.11.11"
 val libuastVersion = "3.3.1"

project/plugins.sbt

@@ -3,4 +3,5 @@ addSbtPlugin("net.virtual-void" % "sbt-dependency-graph" % "0.8.2")
 addSbtPlugin("com.jsuereth" % "sbt-pgp" % "1.0.0")
 addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "1.1")
 addSbtPlugin("com.thesamet" % "sbt-protoc" % "0.99.16")
+addSbtPlugin("com.typesafe.sbt" % "sbt-git" % "0.9.3")
 libraryDependencies += "com.thesamet.scalapb" %% "compilerplugin" % "0.8.3"