Allow adding some custom text in header or footer

I created the patch for this issue that include also path #2 from this issue ([https://drupal.org/i/3359436] Template suggestion based on view display id).
This patch add two text box and two checkboxes for header and footer in settings form, also template suggestion based on view display id for header, content and footer. Please review.

Updated previous patch with templates create.

Thanks for a great idea, bvakulin. Added this feature in the version 2.2.0. Notice that if page numbering is enabled, footer text will override it.

Automatically closed - issue fixed for 2 weeks with no activity.