fix unspents selection target

Summary:
commit 1248530 introduced a bug where we would get all unspents instead of setting a target
this fixes it

Reviewers: ben

Reviewed By: ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1300

calculate fees using tx bytes without rounding up to the nearest kb

Summary: we were rounding up to the nearest kb, which was causing calculation of higher fees than needed.

Reviewers: ben

Reviewed By: ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1298

expose the feeRate used when creating transactions

Summary: expose the feeRate used when creating transactions

Reviewers: jameson, ben

Reviewed By: ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1291

sdk to reconstruct an approval tx

Summary:
reconstruct an approval transaction (but do not send it).
this may be used in cases where a user has approval access but not the private keys (someone else must construct the tx for him)

Reviewers: barath, mike, gavin

Reviewed By: gavin

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1243

exclude change unspents from minconfirms check

Summary:
when minConfirms=1 is passed in to the transaction builder, it will reject all unspents without a confirmation.
this change allows the selection of unspent inputs on change (unspents from transactions sent from the same wallet).

Reviewers: ryan, ben

Reviewed By: ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1209

pending approvals sdk changes

Summary: pending approvals sdk changes

Reviewers: ryan, ben

Reviewed By: ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1159

accept double slashes in bitgo express urls

Summary: be more robust in bitgo express urls with double slashes

Reviewers: ben, ryan

Reviewed By: ryan

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1129

add "validate" parameter to bypass redundant verify

Summary:
In order to optionally make the transaction builder create and sign
transactions faster, we add a new "validate" parameter to createTransaction and
signTransaction. In createTransaction, when set to false, this indicates to bypass the address
validation, saving some bip32 calculations. In signTransaction, when set to false, it indicates to
bypass signature validation. There is also a global config to change the default from true to false.

Reviewers: ben, benchan

Reviewed By: benchan

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1114

expose unconfirmed receives and sends on wallet

Summary: expose unconfirmed receives and sends on wallet

Reviewers: ryan, ben

Reviewed By: ryan, ben

Subscribers: ben

Differential Revision: https://phabricator.bitgo.com/D1119

rev version to push