Add method to set curve name and id

[datnguyencse]

Neo using prime256v1 so I have added new method to MoneyTree to set the curve name and id.
Tested with prime256v1 with node_for_path function.

[coveralls]

Coverage decreased (-0.2%) to 99.215% when pulling e5ba806 on datnguyencse:secp256r1 into 2686577 on GemHQ:master.

[datnguyencse]

Some path return incorrect public key for same master pub/priv key.
Example:
Path 'm/0/2':

----------- Prime256v1: Ruby Priv to Addr for path 'm/0/2' ------------
prik: fc72877a77ca04fc2ec4a970284e2987501aa2c16964b10d5d5394a7969c6fd2
wifk: L5gSDcGVPNM6X5njUBzJGXqM2cUsNdyCPgWTBTo1nhaFnDDsgJ1L
pubk: 024067d37568bae4d79565e05d342a628a913b74b7e9b99086d98972489ee96e9c
addr: AMiH61hvJesiXRnLr4KQFmDz2mTgrnFnfb

----------- Prime256v1: Ruby Pubk to Addr for path 'm/0/2' ------------
pubk: 024067d37568bae4d79565e05d342a628a913b74b7e9b99086d98972489ee96e9c
addr: AMiH61hvJesiXRnLr4KQFmDz2mTgrnFnfb

Path: 'm/0/4' return incorrect address for same path

----------- Prime256v1: Ruby Priv to Addr for path 'm/0/4' ------------
prik: 29cfcd12dc8c81a844c1f7ce325e71e2d483b91d9b43a8a788921bf8dda8d9d4
wifk: KxczDtbZgz4KoC1nPdGuhUKhwBrXZMbn2TcMaDdJX7BMSXwNBJgK
pubk: 02efad86864c7176777a05d491543f01b597688a72fd8c2d8853306e6b2d719b80
addr: ARQE2SofSmpX8iBvo4hCuiF6ijQ2SRidVF

----------- Prime256v1: Ruby Pubk to Addr for path 'm/0/4' ------------
pubk: 02f6b6822a72e4026a4153dcfc3593731727a3e5e745f9c036349517131b55ff3f
addr: AP2Q8MZPRHFP5ymKpY75nh4vGmXHREzakv

Source code:

require 'money-tree'
require 'bitcoin'
require 'byebug'

DEFAULT_ADDRESS_VERSION = '17'
PUSHBYTES33 = '21'
CHECKSIG = 'ac'

path = "m/0/4"

MoneyTree.setCurve('prime256v1', 415)
master_public_key = "xpub661MyMwAqRbcGTJx1g8LZPnRgrAZYnHo8exqQVQinkQjKQQ8SvX6UCcWNgjBPqmKQdhq4MLHMxSedwxFfsmzuGr8F6RLyd87kHpkHFgP3KX"
master_private_key = "xprv9s21ZrQH143K3yEUuebLCFqh8pL59KZwmS3Ec717EQskSc4yuPCqvQJ2XRe68rNth2ouPbgPE14PUDNe9zS57mjkjajASfvbLn457VZz62E"

puts "\n----------- Prime256v1: Ruby Priv to Addr for path '#{path}' ------------"
# Using private key
child_pri_node = MoneyTree::Node.from_bip32(master_private_key).node_for_path(path)
puts "prik: " + child_pri_node.private_key.to_hex()
puts "wifk: " + child_pri_node.private_key.to_wif()
puts "pubk: " + child_pri_node.public_key.to_hex()
puts "addr: " + Bitcoin.encode_address(Bitcoin.hash160(PUSHBYTES33 + child_pri_node.public_key.to_hex() + CHECKSIG), '17')

# # Using public key
puts "\n----------- Prime256v1: Ruby Pubk to Addr for path '#{path}' ------------"
child_pub_node = MoneyTree::Node.from_bip32(master_public_key).node_for_path(path)
puts "pubk: " + child_pub_node.public_key.to_hex
puts "addr: " + Bitcoin.encode_address(Bitcoin.hash160(PUSHBYTES33 + child_pub_node.public_key.to_hex + CHECKSIG), '17')