Add Gradle build

Fixed warnings about missing deprecation annotation and variable name in
one test failing on Java greater version 9.

This commit is simpler then
5847ee4d97

.gitattributes

@@ -0,0 +1,6 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# These are explicitly windows files and should use crlf
+*.bat           text eol=crlf
+