Release 0.3.0

Changes this version:

• Renamed time() to get_time() to avoid a naming conflict (@RobinMeis)
• Added more checks for missing values in gpsd responses (@baftek and @nickoala)
• Changed print calls to logger (@llazzaro)
• Added a valid_sats property to get the number of actually used sats(@domschl)

Release 0.2.0

This release adds support for GPS time thanks to @richteelbah