Send to main admin email if new affiliate email is enabled

[epiksel]

No description provided.

[opencart]

sorry there are to many changes that need to be merged. i can not see what's going on

[epiksel]

I merged updates now.

[maddes]

The whole idea is to send an email to the admin when an affiliate registers.

• upload/catalog/controller/feed/google_sitemap.php
  • FIX: replaced '&' for '&'
• upload/catalog/controller/product/search.php
  • FIX: replaced the hardcoded string 'tag -' for the new language string $this->language->get('heading_tag')
• upload/catalog/language/english/mail/affiliate.php
  • ADDED: New strings for administrator email (to send when a new affiliate is registered)
  • The first 5 lines modified on this file are not really modified, just the alignment of the assignment changed.
• upload/catalog/language/english/product/search.php
  • ADDED: New string for heading tag
• upload/catalog/model/affiliate/affiliate.php
  • The actual email sending logic.

[epiksel]

Sent pull request again #727