Support combined datetime format with subseconds (yyyyMMddhhmmss.SSS)

[dferstay]

We have support for a unixy combined timstamp format of the form yyyyMMddhhmmss

However, some systems log with subseconds appended, for example:

20140722105203.364

The above should parse as: "2014-07-22 10:52:03.364 +0000 UTC"

But parsing fails with the error:

parsing time "20140722105203.364": month out of range