Bug Fix en_SG mobile number generation

[ziming]

Singapore mobile number only starts with 8 or 9. Not 7. The 2nd digit is never a 9 as well

See: http://en.wikipedia.org/wiki/Telephone_numbers_in_Singapore#Numbering_plan

Hope it helps!

8zxx xxxx - Mobile and Data Services

9yxx xxxx - Mobile, Data Services and Pager (until May 2012)

Which also means:

8[1-8]xx xxxx - Mobile and Data Services

9[0-8]xx xxxx - Mobile, Data Services and Pager (until May 2012)

x denotes 0 to 9
y denotes 0 to 8 only
z denotes 1 to 8 only

[ziming]

Hmm. How do I add the bug label? @fzaninotto

[pimjansen]

Thanks for your contribution!