Update README
Update README

Turned "downloads area" into link to releases page
Removed install albacore instruction
Removed submodule init instruction (submodule pulled in 2ab0d50b59)
Updated open solution instruction to VS2012 as sln file is 2012

khellang/structuremap,petemounce/structuremap,zhangwei900808/structuremap,hp4711/structuremap,DixonDs/structuremap,DixonD-git/structuremap,hp4711/structuremap,NightOwl888/structuremap,zhangwei900808/structuremap,petemounce/structuremap,khellang/structuremap,DixonDs/structuremap,hp4711/structuremap,zhangwei900808/structuremap,petemounce/structuremap,DixonD-git/structuremap,DixonD-git/structuremap,DixonD-git/structuremap,NightOwl888/structuremap,zhangwei900808/structuremap,NightOwl888/structuremap,petemounce/structuremap,NightOwl888/structuremap,hp4711/structuremap