Merge pull request #154 from maraoz/refactor/browser-build

Refactor/browser build
selectUnspent function and tests
unworking, direct copy of BIP 32 implementation

This BIP 32, or HD wallet implementation is directly copied from this repo:

https://github.com/sarchar/brainwallet.github.com/tree/bip32

It does not actually work with this commit, since it is designed to work with
bitcoin-js in the browser. It needs to be modified to work with bitcore in node
and the browser.
tx creation working. more tests needed
#create for Transaction and tests
#create for Transaction and tests
#create for Transaction and tests
add comment to generate hardcoded dara
remove outdated example
add example to createKey
fix variable names
add test for #network in Address
add uncompressed key generation example
add network detection in private key and tests
ignore tags file
add TX signing. Support to p2pubkeyhash
add limit to try-verify loop
fix error in commit
remove uncompressed key example
update version to 0.1.8

Changes since version 0.1.7
* Refactor browser building
* Examples of signing transactions
* Key interface is now bitcore.Key, not bitcore.KeyModule.Key
** bitcore.KeyModule is deprecated
* Bug fixes