Doc: connecting iOS devices

Describe Qt Creator support for developing for iOS.

Change-Id: I5d993e343f4f00a09b4c29de6402a338a8011af4
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>
Reviewed-by: Geir Vattekar <geir.vattekar@digia.com>
Doc: Add iOS to supported target platforms

Reformat the table, as it was becoming too wide.

Change-Id: I6c8a41c812ceb8d3075def936b52c80af904ef27
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>