fix mapsurfer contour layer detection
make only acutal text-part of (short) PopupIcons clickable

I see that icons must have a fixed width in order to center them. But it resulted in the whole area being clickable (even the transparent areas right and left of the text). This behaviour is especially confusing if texts are short, but right next to each other.

This uses [pointer-events](http://caniuse.com/pointer-events) to make the transparent areas right and left of PopupIcons non-clickable. And it doesn't harm older browsers.
Merge pull request #29 from tyrasd/patch-1

make only text-part of (short) PopupIcons clickable
1.1.2-dev, update changelog
update proprietary layer in mapbbcode-window
update build
panelHook method for params, refine params API, eachLayer for control
Length plugin
update build and changelog
add hike&bike map
add button measurement
remove leaflet.draw dependency for param.length
more proprietary layers (fix #30); layerList improvements
fixed #31: no more extra includes
update build
fix #31, add hidden map example
ref 2gis library in readme
add edit link to attribution by default, fix #18
removed unusued ui parameter from param.length
refactor param.length a bit