Fix several Austrian numbers

1 (Vienna) phone numbers can be from 4-13 digits long (including local
code)

Examples:
- +43-1-515180
http://www.marriott.com/hotels/travel/vieat-vienna-marriott-hotel/
- +43 (1) 727 27-0 http://www.austria-trend.at/hotel-messe-wien/en/

681 and 699 mobile phone numbers are 8 digits long (excluding prefix)

Examples:
- +43 699 1196 1457 http://www.ecomal.com/en/contact/austria/
- Other numbers reported to our DNSimple customer care

688 mobile phone numbers are 7 digits long (excluding prefix)

Examples:
- +43 688 930 7 572 http://www.mhdrinks.com/index.php/ct-menu-item-3
- Other numbers reported to our DNSimple customer care
Merge pull request #177 from aetrion/bugfix-austria

Fix several Austrian numbers