Yandex overlay is broken

[johnd0e]

We have no documentation, but I suppose that overlay option is made exclusively for traffic layer, to show traffic w/o map tiles, which is great for overlay.

But official example yandex.html just does not work.

I see there 2 problems:

1. leaflet-plugins/layer/tile/Yandex.js

   Line 143 in 4d4bf55

    if (this._type === 'yandex#null') { 

   
   This condition is never true, 'cause 'null' is not in list:
   

   leaflet-plugins/layer/tile/Yandex.js

   Lines 18 to 23 in 4d4bf55

    possibleShortMapTypes: { 
    	schemaMap: 'map', 
    	satelliteMap: 'satellite', 
    	hybridMap: 'hybrid', 
    	publicMap: 'publicMap', 
    	publicMapInHybridView: 'publicMapHybrid' 

   
   Easy to fix.
2. Even if we fix 1st issue, our overlay stays hidden over baselayer.
   It's possible to put it in front by random clicking, but it's not reliable.