Configure parsers for Mesos agents and scheduler

[mwl]

Mesos agent

timestamp: MMdd HH:mm:ss[.SSSSSS]
regex: (?<level>\w)(?<@timestamp>\d{4}\s\S+)\s+(?<thread_id>\S+)\s(?<file>\S+):(?<line>\d+)]

Edit: Updated regex, according to #13 (comment)

[ssiahetiong]

Tested with DCOS 1.9, regex should be:
(?<level>\w)(?<@timestamp>\d{4}\s\S+)\s+(?<thread_id>\S+)\s(?<file>\S+):(?<line>\d+)]

[mwl]

@ssiahetiong Makes sense. Thanks! I'll update the description