adding instructions for local building

Author: madhephaestus

bindings/java/README.md

@@ -1,3 +1,21 @@
 ## Manifold3d Java Bindings
 
-[![Clojars Project](https://img.shields.io/clojars/v/com.github.madhephaestus/manifold3d.svg)](https://clojars.org/com.github.madhephaestus/manifold3d)
+[![Clojars Project](https://img.shields.io/clojars/v/com.github.madhephaestus/manifold3d.svg)](https://clojars.org/com.github.madhephaestus/manifold3d)
+
+##Developemnt
+
+for local install to maven of a snapshot run:
+
+```
+bash bindings/java/scripts/localSnapshotInstall.sh 
+
+```
+
+and see the printouts:
+
+```
+Clojar Java /home/hephaestus/bin/java21/
+Clojar Version: 3.4.0-46a5518e-SNAPSHOT
+```
+
+That means you can run a local build with version `3.4.0-46a5518e-SNAPSHOT` which means it is commit 46a5518e which is ahead of the tag 3.4.0.