With this commit, a user can now specify a regex when specifying custom
permissions for an LNC session. This regex will be used to select
permissions for URIs that match the regex.
Remove the use of the UI password from litcl. Use the litd macaroon
instead. Note, this means that in stateless mode, litcli won't have a
macaroon to use on disk and one must be baked specifically.
The default expiry of one hour was way too short for anything practical
and we increase it to 90 days which is almost three months.
The user can still override this value manually by specifying the flag.
To avoid the macaroon parsing to fail in session.IsSuperMacaroon(), we
want the dummy macaroon to be formally valid (meaning, it can be parsed)
but not actually valid (meaning, it will fail the signature verification
since we don't have the root key for it anywhere).
Add flag to litcli so that we can create sessions of the admin or
readonly macaroon type through the cli.
This commit also results in it no longer being possible to create a
UIPassword session through the CLI.
