reformat markdown code

backend/doc/roles.md

 
 |                               | Normal User | Managers    | Admin          |
 |-------------------------------|-------------|-------------|----------------|
-| slug                            | users       | managers    | administrators |
+| slug                          | users       | managers    | administrators |
 |-------------------------------|-------------|-------------|---------|
 
 
 |-------------------------------|-------------|-------------|---------|
 | create workspace              |  no         | yes         | yes     |
 | invite user to tracim         |  no         | yes, if manager of a given workspace         | yes     |
-  delete workspace              |  no         | yes, if manager of a given workspace         | yes     |
+| delete workspace              |  no         | yes, if manager of a given workspace         | yes     |
 |-------------------------------|-------------|-------------|---------|
 | set user global profile rights|  no         | no          | yes     |
 | deactivate user               |  no         | no          | yes     |