Fixes up local mobile phone numbers to a uniform text format.
Usage
fix_mobile(x)
Value
The updated vector, usually the column of a data frame.
Arguments
x
A character vector of numerical strings.
Details
This format is specific to that used in a given location - for
now the function is useful only for Nigeria mobile numbers, which come in
the format expressed by the regex pattern "^0[7-9][0-1][0-9]{8}$".