Bug#721077: Upstream using grunt

[Daniel Pocock <daniel@pocock.com.au>]

Upstream uses Grunt

Grunt isn't packaged yet
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=673727

I've submitted a Makefile so JsSIP can build without Grunt
https://github.com/versatica/JsSIP/pull/152

Upstream packaging issues discussed here:

https://github.com/versatica/JsSIP/issues/77


Google Closure Compiler is a build dependency.  It is broken and its
runtime dependencies are not declared:
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=705565

so we are declaring those build dependencies too and working around it
in the rules file by explicitly supplying the JVM command line