Before this change the Features() method would return a different Fs
to that the Features() method was called on if the remote was
instantiated on a file.
The practical effect of this is that optional features, eg `rclone
about` wouldn't work properly when called on a file, and likely this
has been causing low level problems for users of these backends for
ages.
Ideally there would be a test for this, but it turns out that this is
really hard, so instead of that all the backends have been converted
to not copy the Fs and a big warning comment inserted for future
readers.
Fixes#2182
This unifies the 3 methods of reading config
* command line
* environment variable
* config file
And allows them all to be configured in all places. This is done by
making the []fs.Option in the backend registration be the master
source of what the backend options are.
The backend changes are:
* Use the new configmap.Mapper parameter
* Use configstruct to parse it into an Options struct
* Add all config to []fs.Option including defaults and help
* Remove all uses of pflag
* Remove all uses of config.FileGet
It is unnecessary to notify the node.Parents, because a cahnge event is
generated for all involved files and folders in a move from d1/f1 to
d2/f1. There will be a event for d1, d2 and f1.
Additionally a duplicate notification is resolved when them empty string
is in pathsToClear.
Related to #2006
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.
The new code layout is documented in CONTRIBUTING.
