tests: adds r = s = -n ecdsa verify test case
ecdsa: add SEC annotations for verify
ecdsa: add further (missing) annotations from 1.4.x
1.0.2

Signed-off-by: Kyle Drake <kyle@kyledrake.net>
HDNode: assert chain code length
HDNode: add neuter functionality
tests: use neutered rather than import/export
hdnode: add deprecation message for isPrivate
Merge pull request #248 from dcousens/hdnode

HDNode / BIP32 Neutering