Add alerting and getinfo_MP

Please see notes here guys http://pastie.org/pastes/9733526/text?key=luz9fdv1whtvfhn1sjvckg

Before merging can we grab an hour to build this and run over how it works/test it out.

Thanks
Z
As we evolve sure, and thanks for link.  In these early days, wanted to use a model that allowed one of the core devs to issue an 'on the spot' alert easily and quickly.  When more stable move to multisig and multiple signatories on alerts.

P.S. you know it's your builder I've been using to build the alert txs btw :P thanks for a very useful tool!