MANTA-2081 update node-manta for access control and subusers
MANTA-2284 mchmod =<foo> removes all tags from a resource
MANTA-2289 mchmod +-foo replaces all tags
make mchmod +/- failures clearer
mchmod look at the correct error
support old client.user usage
add support for user-generated presigned URLs
Merge branch 'access-control'

Conflicts:
	lib/client.js
fix ~~/ path resolution
version bump
add manpage for mchmod and update manpages for new RBAC options
#197 fix ~~/ handling for mjob assets
version bump
DOC-590  Replace /$MANTA_USER with ~~
DOC-590 Replace MANTA_USER with MANTA_ACCOUNT
DOC-590  Add explanation of ~~ and MANTA_USER/MANTA_ACCOUNT to man files
DOC-590 Remove para abou MANTA_ACCOUNT/MANTA_USER
Merge branch 'DOC-590' Use ~~ in man page instead of MANTA_USER
Update CHANGES.md
DOC-593 back to MANTA_USER