[update] Squashed qtlocation/ changes from ea5f625..5e27d57.

This updates to the latest qtlocation/stable branch (to become Qt 5.2),
with the necessary changes to support building against Qt 5.1.

The Qt Location library has been split into Qt Positioning and
Qt Location. This breaks binary and source compatibility with the
previous package.

Going forward the Qt Positioning API is likely to be stable and is
currently the same as what will be included in Qt 5.2. The Qt Location
API is not stable and is likely to change upstream before it is
officially released.

5e27d57 Move tilecache storage to a standard location
deccc5f Make compile after recent V4 API changes
e0256ec Doc: Setting \qtvariable to "positioning" instead of "location"
0ed9f74 Improve area monitoring API.
87ce030 Return NaN if position info source doesn't have an attribute.
74a2769 Fix MapGestureArea consuming mouse events.
db8c9f1 Improve definition of projects belonging to QtPositioning & QtLocation
e31739e Fix broken polygonline and polygonitem for ARM.
8f9b145 Fix Geoclue plugin when used with slow Geoclue providers.
67430cb Fix assert error caused by MapItemView.
eeb0f97 Fix conditional expression.
d037cbc Fix comment in copy and pasted code.
5611ad3 Implement socket NMEA source.
d26ab7e Revert "Temporarily fix qtlocation against a non-broken qtbase."
fc53ebd Fix some name inconsistencies in QtLocation
9f98392 Update the cmake test for the location modules.
d35d280 Split QtLocation into QtPositioning and QtLocation
ea5f625 Temporarily fix qtlocation against a non-broken qtbase.