This branch may be submoduled into truffle and other solidity projects.
To do so:
cd contracts
git submodule add -f -b 1.0.0-embedabble git@github.com:summa-tx/bitcoin-spv.git
git submodule update --init --recursive
This should place a contracts/bitcoin-spv
folder in your contracts folder.
Truffle should be able to find this :)