flight-upload.js: move times checking to another method
flight-upload.js: check times when setting via setSelection, too.
baro.js: add method to return flot placeholder
baro.js: setFlightTimes returns actually set times (checked by the plugin)
upload.js: initBaro returns dict with flot and times
assets: use forked version of bootstrap-timepicker with some bugfixes
upload.js: bind timepicker updates to barogram