Conditionally use Drupal's jQuery only if available

[colemanw]

Overview

Fixes dev/drupal#68 and guards against javascript errors.

Before

Javascript error if Drupal's jQuery not loaded.

After

No error.

[civibot]

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[adixon]

Thanks, this looks right. How about updating the comment above the change to the effect that jQuery may not be loaded (in which case, we don't need to worry about the toolbar).

[colemanw]

@adixon done.

[adixon]

Readable and functional, who could ask for more?