add stealth_address class.
add stealth.hpp to wallet.hpp
install wallet/stealth.hpp header
stealth stubs
temporary ec math abstracted API. once we migrate to non-openssl code, I suspect the API will change/improve.
Revert "temporary ec math abstracted API. once we migrate to non-openssl code, I suspect the API will change/improve."

This reverts commit 21204fb3ca1b5d6c6a2f7bb0523af02ffb36916e.
Port hd_keys to the new ec_keys
Switch key_formats to the new ec_keys system
Use to_data_chunk in key_formats
updates for latest ec stuff in libbitcoin
change data_chunk to ec_point in stealth stuff.
Move the URI examples into the unit tests
stealth functions.
add sx command to generate addresss to test.
use preferred 'secret' nomenclature over privkey. it's more consistent with rest of libbitcoin and has more contrast with 'pubkey'
made stealth_address a simple struct to avoid tons of redundant set/get methods.
Use the new ec_add function names
encoding stealth address.
Merge branch 'develop' of github.com:libbitcoin/libwallet into my_develop
update for last minor changes to ec function names.