Add missing range for Georgian operator - Magticom

[kostamilorava]

• Country: Georgia
• Example number(s) and/or range(s): 511123123
• Number type ("fixed-line", "mobile", "short code", etc.): mobile
• For short codes, cost and dialing restrictions: NO
• Where or whom did you get the number(s) from: -
• Authoritative evidence (e.g. national numbering plan, operator announcement): -
• Link from demo (http://libphonenumber.appspot.com) showing error: -

This PR adds support for phone numbers starting with 511. Magticom has this index 10 or 15 years already, it's not new.

You can check that this index is valid here (Official website, click on ALL to see 511 in dopdown list) and here

[google-cla]

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