[FEATURE] RT-2463 LESS: Generalize currency colors
[FEATURE] RT-2463 LESS: Generalize currency colors

Colorization by currency is no longer used by Balance tab only, but also
by Balances sidebar widget.

mrajvanshy/ripple-client,yongsoo/ripple-client,ripple/ripple-client,ripple/ripple-client,wangbibo/ripple-client,vhpoet/ripple-client,Madsn/ripple-client,xdv/ripple-client,h0vhannes/ripple-client,MatthewPhinney/ripple-client,vhpoet/ripple-client,h0vhannes/ripple-client,h0vhannes/ripple-client,xdv/ripple-client,xdv/ripple-client,wangbibo/ripple-client,arturomc/ripple-client,wangbibo/ripple-client,bsteinlo/ripple-client,darkdarkdragon/ripple-client,mrajvanshy/ripple-client,ripple/ripple-client,h0vhannes/ripple-client,darkdarkdragon/ripple-client,mrajvanshy/ripple-client,yongsoo/ripple-client,darkdarkdragon/ripple-client,yongsoo/ripple-client,ripple/ripple-client,bsteinlo/ripple-client,vhpoet/ripple-client,wangbibo/ripple-client,vhpoet/ripple-client,darkdarkdragon/ripple-client,yongsoo/ripple-client,arturomc/ripple-client,mrajvanshy/ripple-client,MatthewPhinney/ripple-client,MatthewPhinney/ripple-client,Madsn/ripple-client,xdv/ripple-client,Madsn/ripple-client,MatthewPhinney/ripple-client,arturomc/ripple-client,arturomc/ripple-client,Madsn/ripple-client