Transport: Added a peer pool to maintain a set of connected peers
Transport/Pool: Use sinon for tests.
Transport/Pool: Added tests to check that new addrs are added
Transport/Pool: Mark internal functions
Merge pull request #744 from braydonf/feature/transport-peer-pool

Transport: Added a peer pool to maintain a set of connected peers. Closes #724
trying to fix ScriptInterpreter
add script_interpreter
refactors and fixes for script interpreter
adding some signature methods for script interpreting
make creation methods class methods
Pubkey -> PublicKey
pass some more tests
trying to fix OP_CHECKSIG script evaluation
import Sighash
some more passing tests
fix some more tests
all script_valid tests passing!
generalize script tests
add Script#checkMinimalPush tests
fix all script validation tests, yay!