No functional changes.
As pointed out in lightwalletd/pull/469, the errors package we're using
has been deprecated, so this commit updates the code to use "errors"
instead of "github.com/pkg/errors". Same with "io/ioutil", which has
been superceded by "os".
This causes lightwalletd to discard cached blocks at the given height
and beyond. This in turn causes it to re-fetch those blocks from zcashd.
It's similar to --redownload, except that option discards all blocks
(equivalent to --sync-from-height 0, but the existing --redownload is
retained for compatibility).
This is mostly intended for testing. It's sometimes useful to force the
node to (re)sync some recent blocks, but redownloading all of them takes
around an hour.
Larry Ruane
Larry Ruane