MAC changes now apply to /etc/network/interfaces; fix docs.

- The sed command shouldn't've started with "^". (165)
- Don't "wc -l" the wired interface list. (23)
- Replace deprecated "service networking restart". (39)
- Tabs to 4 spaces. (everywhere)
Moved provide-source from 60 to 99 to capture all packages.
Merge pull request #13 from NickDaly/master

MAC changes now apply to /etc/network/interfaces; fix docs.