[GR-19220] Spin configuration (#2297)

PullRequest: truffleruby/2494

Author: eregon

.spin/bin/bootstrap

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+set -ex
+source .spin/bin/env
+
+sudo apt-get install -y cmake libssl-dev libz-dev python
+
+jt install jvmci
+jt install eclipse
+jt mx sforceimports
+jt build
+jt ruby --version

.spin/bin/env

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+function jt {
+  ruby tool/jt.rb "$@"
+}