Bump src/loggregator

Bump :
  Johannes Tuchscherer:
     Merge pull request #26 from mheath/time-secfrac
  Mike Heath:
     Use a static date to allow for a deterministic message length.
     Added support for fractional seconds.
  Johannes Petzold:
     Remove integration tests from travis build
     remove unused build logic

Signed-off-by: John Tuley <jtuley@pivotallabs.com>