Added Open/Save functionality to the menus
Added file filters for later use
Renamed example chart to comply with later save extension
Created the Open dialog
Created ag_app_open_chart()

It can open files from both the command line or the Open dialog
Added altitude to the saved chart example
Added libxml2 as a build dependency
Now testing for libxml in main()
XML processing for chart open functionality is finished
Typo fix
Created functions ag_window_{set,get}_chart()
Added time zone to example save file
Bug fix for non-existing tags in the save file
Bug fix, added missing variable
Now correctly freeing xml variable in ag_app_open_chart()
Added name, country and city properties to AgChart
Fixed ag_window_set_chart() so it connects the signal handlers well
Created ag_window_redraw_chart() for later use
Chart changing now calls ag_window_redraw_chart()
Created ag_window_update_from_chart() to update form values from the window's chart