handleMapPostrender returns undefined

Without this we get the following warning from the compiler:

JSC_EXPORTED_FUNCTION_UNKNOWN_RETURN_TYPE. Unable to determine return type for exported function ol.control.Control.prototype.handleMapPostrender at ../src/ol/control/control.js line 79 : 51

I'm not sure why explicitely specifying the return type is required here.
GML parser.

This adds a parser (read/write) for GML v2 and v3. GML v3 is limited to the
simple features profile of GML 3.1.1, just like OpenLayers 2 was. This will
be the basis for the WFS parser, but it only makes sense to continue this work
once feature modification (insert, update, delete) is in place in ol3. So the
WFS parser will be another pull request.
incorporate review from @ahocevar
do not specify the source projection in ol.parser.ReadFeaturesOptions anymore
Merge pull request #709 from bartvde/gmlfresh

GML parser (r=@ahocevar)
Accurate hit detection

With this change, hit detection for lines and points gets very
accurate, because the vector renderer instance keeps track of
line widths and point symbol sizes. After doing a bbox query in
the RTree, returned lines and points are evaluated against the
thresholds of their line width or symbol size. The KML example
with its different symbolizers now has getFeatureInfo too to
show this in action.
Store symbol sizes by tile

The reason for this change is that symbolSizes and maxSymbolSize
on the instance will be wrong as soon as the resolution changes
and cached tiles are used. It turned out that the approach used
now has several advantages: smaller symbolSizes objects, no need
to merge symbolSizes objects, and cache management for free (no
risk of memory leaks). Note that the symbolSizes and
maxSymbolSize for each tile are not strictly tile specific -
they represent the rendering pass that created the tile. This
has no negative side effects, and it has the advantage that
there is not a single additional loop needed to create these
structures.
Merge pull request #708 from elemoine/user-extensions

The compilation of ol.js produces a warning
More verbose variable names
Do not change ol.extent.containsCoordinate
Fixing typedef
Fixing typo
Merge pull request #710 from ahocevar/hit-detection

Accurate hit detection. r=@bartvde