update infra
update infra

* submodules/infra 6a8c279...7e7ca12 (3):
  > Merge into master from pull request #38: Fix log level mapping based on the string. (https://github.com/floodlight/infra/pull/38)
  > Merge into master from pull request #37: Simple flag convenience macos.  (https://github.com/floodlight/infra/pull/37)
  > Merge into master from pull request #36: SYSLOG messages are now self-documenting and can be extracted from compi... (https://github.com/floodlight/infra/pull/36)

harfly/indigo,harfly/indigo,harfly/indigo,harfly/indigo