Add Maven POM.

Change-Id: Ide988b8d5a8546894b1e81ce1bf8fb41267c4dc9
diff --git a/.gitignore b/.gitignore
index 0506fc9..bd7fe11 100644
--- a/.gitignore
+++ b/.gitignore
@@ -36,3 +36,7 @@
 
 # Shell
 .envrc
+
+# Maven
+target/
+*.versionsBackup