0.2.1

• Fix heatmap generation error if wifi-survey is run with -S / --no-scan option to disable iwlist scan.
• Implement -b / --bssid option to ensure that scan is against a specified BSSID.
• Implement --ding option to play a short audio file (i.e. a ding) when measurement is finished.
• wifi-heatmap - accept either title or filename as argument