Fix documentation errors.

Change-Id: I16b4f9116a651edaebc54957daf528278785bc55
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
Add direction and vertical speed properties to QML Position type.

The QML and C++ position types now provide the same functionality.

Position attributes are always set/reset on every position update. This
ensures that old values of speed, accuracy, direction, and vertical
speed are not indefinitely reported in QML. Values are set to NaN and if
appropriate the associated is valid property is set.

[ChangeLog][QtPositioning][Position] Added direction and vertical speed
properities.

Change-Id: Ia02da8a5bc1cd68489eb58180986df512c24aa2f
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
Simplify property change logic in Position type.

Removes all member variables and replaces them with a QGeoPositionInfo.
Uses the same value changed and validity changed logic for all
properties.

Change-Id: Ic0420ce7a26da2db12c3eabcad4beac83ea332fe
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>
Fix CoordinateAnimation documentation.

The following issues were fixed:

 * The documentation was declaring that it was it QtLocation instead of
   QtPositioning.
 * Remove module prefix from properties.
 * Change property type to coordinate.
 * Add since tag.

Task-number: QTBUG-36366
Change-Id: I6e3fd81b377f6c9afd188a2695601ab45485d007
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>