(CFACT-162) Update uptime regular expressions for additional formats

In some versions of uptime on some versions of Solaris,
output may differ from what we previously expected. Specifically,
the coreutils GNU version does not include a ',' after 'day(s)', and
in some cases uptime may return a '-' character in the minutes field.

This commit updates the relevant regular expressions so that we can
match and parse these uptime strings.
Merge pull request #240 from whopper/CFACT-162/uptime_format_update

(CFACT-162) Update uptime regular expressions for additional formats