Collection of temporary API hacks in edge

[C0rby]

This issue should contain all the temporary hacks we implemented in the edge branch which should be changed later on.
To not miss anything let's collect them here:

• https://github.com/cs3org/reva/blob/edge/internal/http/services/owncloud/ocs/handlers/apps/sharing/shares/spaces.go#L105-L110
• https://github.com/cs3org/reva/blob/edge/internal/grpc/services/gateway/storageprovider.go#L300-L303
• ...

[kobergj]

Great idea! There a lot. These are the ones I remember having touched recently...

• https://github.com/cs3org/reva/blob/edge/pkg/storage/utils/decomposedfs/spaces.go#L324
• https://github.com/cs3org/reva/blob/edge/pkg/storage/utils/decomposedfs/spaces.go#L627
• https://github.com/cs3org/reva/blob/edge/pkg/storage/utils/decomposedfs/decomposedfs.go#L178
• https://github.com/cs3org/reva/blob/edge/internal/http/services/owncloud/ocdav/spacelookup/spacelookup.go#L46-L53

[C0rby]

#2616

[C0rby]

#2624

[C0rby]

#2666