Script: detect and parse P2SH and multisig scripts
Merge pull request #27 from jgarzik/p2sh-1

Script: detect and parse P2SH and multisig scripts
Merge pull request #28 from jgarzik/sin

Broken SIN stuff
fixed jeff's bug
SIN: spec updated magic number (prefix) to 0x0F
Support SIN keys in wallets.