Fix few bugs on the UI:

- fix karma watch mode
- Fix number vs buildid bug in the build page
- python: add events for new logs
- Fix race condition between event registering and first value got from data api
- fix logviewer so that it does not poll anymore
serialize log append

slave is sending status and stdout in parallel, then the number of line is not handled correctly

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
polish the build page

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>
handle loss of sse connection

In this case, all the bound data must be reloaded, and event listen to again
Implementation is probably a bit inefficient, but its probably better than too complicated

Signed-off-by: Pierre Tardy <pierre.tardy@intel.com>