Fix sort order in Channels and Guide when there are more than 10 subchannels

[xilex 9]

When there are more than 10 sub-channels, the program treats 18.11 as if it should come before 18.1. It should be 18.1 .... 18.9, 18.10, 18.11, etc.

[Luke 37107]

Thanks for the report. We'll take a look.