revert cafile error handling, continue with nil

This reverts commit 2a5e8587f65cac4780647d80b9e48e9695044b58.
Update for recent btcjson API change.

This commit updates the Tx field of the ListReceivedByAddressResult to
TxIDS to mirror the recent change btcjson.
Refactor txToPairs into smaller functions

Also adds tests for those functions, and improve fee estimation.
Make scrypt parameters overridable/optional
Move new addrmgr Options type and default to top.

Default values near the top of the file is preferrable so they are more
easily spotted.
Update unspentOutputs to remove spent unconfirmed outputs
IMPORT PATH MODIFICATION CHANGESET
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Please use this changeset as the first one on top of the conformal codebase.
Note that if there are new imports, they need to be changed as part of this
changeset. In general, use "git rebase" on github.com/conformal's version
and apply this changeset first.
Squash 62 changesets.

Implement voting pools deposit side.
Write a colored coins integration test.

This should prove how IFOC can work with btcwallet.

This closes #62