docs(directive): fixed a minor typo

[suhajdab]

Fixed a minor typo:

• eleent => element

[mary-poppins]

Thanks for the PR!

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Thanks again for your help!

[suhajdab]

Balázs Suhajda

[suhajdab]

And now?

[matsko]

@suhajdab can you style the commit message to follow AngularJS' commit style? https://github.com/angular/angular.js/commits/master

[suhajdab]

@matsko Editing on this page is not enough?
Was trying to push this minor fix via browser only.