Please review.



Quote:



    core: drop NMConnectionProvider and use NMSettings directly
    
    This is not C# but glib. Using interfaces is so cumbersome, that they
    don't simplify code but make it more complicated.
    
    E.g. following signals and its subscribers is complicated enough. It gets
    more complicated by having NM_SETTINGS_SIGNAL_CONNECTION_ADDED and
    NM_CP_SIGNAL_CONNECTION_ADDED. Of course, your favorite IDE has no idea
    about glib interfaces, so figuring out who calls who gets more
    complicated.
    
    This undoes commit 4fe48b1273cff8dde3688a1dc4b7bcbf0a9e16f4. Originally,
    NMConnectionProvider had only one function get_best_connection(). But it
    kept growing and more functions were added.
    
    If we want to ~hide~ certain part of the NMSettings API, we should move them
    to a separate header which gives internal access.