River of Souls v2.837

Added blends to the Radiant side of the river.
Completely redesigned the Dire side of the river.
Recoloured the trees/foliage on the Radiant side.

Fixed an issue with the cave on the direside causing heroes to fall under the map.

![Pic1](http://i.imgur.com/2WeJeKZ.jpg)
![Pic2](http://i.imgur.com/XcCTqlk.jpg)
![Pic3](http://i.imgur.com/1I4fOli.jpg)
![Pic4](http://i.imgur.com/LA8CLBE.jpg)