Refactor out some functions I'm going to use in other git-bb-* scripts

bin/bbhelpers.rb

@@ -0,0 +1,34 @@
+#!/usr/bin/env ruby
+#
+# Copyright 2016 Joe Block <jpb@unixorn.net>
+#
+# License: Apache 2.0, see LICENSE in this repository.
+#
+# Helper functions that are common across the git-bb-* scripts. Admittedly
+# not very pretty.
+
+def git_branch
+  `git rev-parse --abbrev-ref HEAD`.chomp
+end
+
+def git_commit
+  `git rev-parse HEAD`.chomp
+end
+
+def git_remote
+  `git config --get remote.origin.url`.chomp
+end
+
+def git_root
+  `git rev-parse --show-toplevel`.chomp
+end
+
+def openURL(url)
+  if RUBY_PLATFORM.index('darwin')
+    open_command = 'open'
+  end
+  if RUBY_PLATFORM.index('linux')
+    open_command = 'xdg-open'
+  end
+  system("#{open_command} #{url}")
+end