- remove "\r\n" line endings
- colorize <warn> and <error> in red
- extend matching the info levels to include the timestamp. This
(intentionally) will no longer highlight messages from ModemManager,
which don't include a timestamp.
- use "grep -a" so that grep doesn't refuse to work in binary input.
- make the script source-able to only define the NM-colorize and
NM-show-journal
- In case the script is sourced, it also defines a NM-log function,
which does the same as the script itself.
- rename internal functions so that they have names starting with "NM"
in case of sourcing.
