Add "Show SSH Public Key" to new repository form (1.7)

The admin templates are kind of annoying in that if the object doesn't exist
yet, they don't include the object-tools-items block. This meant that the "Show
SSH Public Key" link wasn't shown for the "Add Repository" form.

This change overrides the object-tools block (instead of object-tools-items) to
unconditionally include the <ul>.

Testing done:
Looked at both the "Add Repository" and "Change Repository" forms. Saw that the
SSH key link was present and functional for both.

Fixes bug 3262.

Reviewed at https://reviews.reviewboard.org/r/5626/