Support for MapQuest and Waze mapping services

Also:

• fix for near-zero coordinates handling
• simplified/improved mapping via Bing Maps
• minor amendments to README and action descriptors

Fixes and README improvements

• improve screenshot of extra context menu items
• add zenity window screenshot to README.adoc
• fix file name formatting in zenity window titles
• improve wording in istallation script
• simplify file list in README.adoc

Add screenshot

Add screenshot of new context menu items

Remove intermediate menu

Remove intermediate menu in favor of individual context menu action items

Fixes after IPO :)

• LANGUAGE default value fixed in exif_metadata__settings.bash;
• ancillary scripts renamed;

Initial implementation

Initial implementation.