add ServerGUI.java Util.java

add queryFlightByNo(),transformToFlightInfo() in DB_Operator.java
test successfully
modify some details in DBConnector.java

Signed-off-by: jsxhhyf <jsxhhyf@gmail.com>
Merge remote-tracking branch 'choose_remote_name/master'

Conflicts:
	FIT5183A1/src/util/DBConnector.java

Signed-off-by: jsxhhyf <jsxhhyf@gmail.com>