Add MapMarker and MapBubble classes

These are base classes intended to create markers associated with
content rich popovers.

https://bugzilla.gnome.org/show_bug.cgi?id=722871
Refactor user location marker to support bubble

https://bugzilla.gnome.org/show_bug.cgi?id=722871
Replace MapLocation with SearchResultMarker,Bubble

https://bugzilla.gnome.org/show_bug.cgi?id=722871
route: Add support for via points

Route query and service have now support to via points.
The routing query has no more 'from' and 'to' properties but
it has a new property called 'points' that is an array of places.
The routing query allows all the basic operations on points.
A query is legal if all the places are defined.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
sidebar: Add via points support

Remove the statical entries called 'to' and 'from'.
It is now possible to add and remove rows to the sidebar form.
Every row contains an image label and a PlaceEntry,
that on change modify the query property 'points'.
The first row has a button for adding new rows.
The via point's rows have a button for removing them.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
sidebar: add indications about distance and time

Add a new row in the sidebar that contains information about the
estimated time for reaching the destination and the distance to it.
Every instruction containes information about the distance.
There are two new utility functions for writing in the correct format
the distances and the estimated time.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
Change route path width and color

The routing path now is blue and the width is set to 5px.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
routing: New markers for turnpoint

These markers are showed if a turnpoint is a stop.
The markers are draggable and after drag is finished a new route is
calculated and shown.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
routing: Show turnpoint marker on instruction selection

https://bugzilla.gnome.org/show_bug.cgi?id=731068
sidebar: Small graphical changes

Add a new separator between the sidebar form and
the instruction list.
Remove a glitch on mouse hover on the form.
The sidebar form is now transparent.

https://bugzilla.gnome.org/show_bug.cgi?id=731068