Merge pull request #88 from jimmysong/87

Issue #87: Make a method that takes a pycoin tx and converts to a compos...
mempool coloring update
Merge branch 'master' of github.com:bitcoinx/ngcccbase
ComposedTxSpec refactoring
fix
Issue #89: backward scan coloredcoinlib

Add a recursive function to scan all matching inputs before computing the colorvalues.
Each input in turn needs to have the colorvalues of the matching inputs as well.