WL#1628: Change to use my_strtoll10()

We should change all usage to my_strtoll, my_strntoll, my_strontoull to
use my_strtoll10() instead.

The reson for this is that my_strtoll10() is faster and more general for 10 base
strings.

Things to do:

- Add my_strtoll10() interface to the character set functions in strings/ctype-.
  A lot of these can be mapped to global my_strtoll10() version
- Change all code that uses base 10 to use my_Strtoll10 or  
CHARSET_ÌNFO->my_strtoll10()