XWIKI-9429: Display the "add wiki" link only if the user has the "createwiki" right and if a wiki template is created.
XWIKI-9429: Display the "add wiki" link only if the user has the "createwiki" right and if a wiki template is created.

* Removing a useless line.
XWIKI-9429: Display the "add wiki" link only if the user has the "createwiki" right and if a wiki template is created.

* Add a comment to explain how $hasCreateWorkspace is determined.
Merge pull request #155 from gdelhumeau/XWIKI-9429

XWIKI-9429: Display the "add wiki" link only if the user has the "createwiki" right and the workspaces application is correctly installed