fix warning
removed unused reference
fix redirect output of fsc --server to fsc --resident

console output from server was not redirected to resident
fix unused value warning
ignore ISymWrapper dll if CROSS_PLATFORM_COMPILE

ignore ISymWrapper assembly if defined CROSS_PLATFORM_COMPILE
use ISymWrapper assembly only on Windows
Merge branch 'warnings_are_bad' of https://github.com/enricosada/fsharp into warnings_are_bad
Merge branch 'warnings_are_bad' of https://github.com/enricosada/fsharp into warnings_are_bad
update sln to visual studio 2013 update 1
set warnings as error