Additional Maryland (US) cities

[dremex]

Adds a few missing Maryland (US) cities.

• Bethesda - https://nominatim.openstreetmap.org/details.php?place_id=197606619
• Catonsville - https://nominatim.openstreetmap.org/details.php?place_id=197559674
• Columbia - https://nominatim.openstreetmap.org/details.php?place_id=197560413
• Elkridge - https://nominatim.openstreetmap.org/details.php?place_id=198331568
• Ellicott City - https://nominatim.openstreetmap.org/details.php?place_id=197795303
• Germantown - https://nominatim.openstreetmap.org/details.php?place_id=197795015
• Glen Burnie - https://nominatim.openstreetmap.org/details.php?place_id=197595760
• North Bethesda - https://nominatim.openstreetmap.org/details.php?place_id=198076874
• North Laurel - https://nominatim.openstreetmap.org/details.php?place_id=197606779
• Silver Spring - https://nominatim.openstreetmap.org/details.php?place_id=198331684
• Waldorf - https://nominatim.openstreetmap.org/details.php?place_id=198331852