Updates to .gitignore
Updates to .gitignore

- Ignore new files introduced in fsharp4 branch, as they might be hanging around when you switch to master
- Ignore some test directories
- Ignore various other stuff already marked in fsharp4
 (changeset 1401726)

syeerzy/visualfsharp,dsyme/FSharp.Compiler.Service,rneatherway/FSharp.Compiler.Service,matthid/FSharp.Compiler.Service,cloudRoutine/FSharp.Compiler.Service,forki/FSharp.Compiler.Service,ncave/FSharp.Compiler.Service,forki/FSharp.Compiler.Service,forki/FSharp.Compiler.Service,syeerzy/visualfsharp,sergey-tihon/FSharp.Compiler.Service,wk-j/fsharp,Heather/fsharp,syeerzy/visualfsharp,rojepp/FSharp.Compiler.Service,mafiya69/fsharp,brettfo/visualfsharp,yever/FSharp.Compiler.Service,cloudRoutine/FSharp.Compiler.Service,syeerzy/visualfsharp,dsyme/fsharp,rojepp/FSharp.Compiler.Service,Jand42/FSharp.Compiler.Service,yever/FSharp.Compiler.Service,brettfo/visualfsharp,dsyme/fsharp,0x53A/FSharp.Compiler.Service,ncave/FSharp.Compiler.Service,cloudRoutine/FSharp.Compiler.Service,dsyme/FSharp.Compiler.Service,vasily-kirichenko/FSharp.Compiler.Service,matthid/FSharp.Compiler.Service,Jand42/FSharp.Compiler.Service,alfonsogarciacaro/FSharp.Compiler.Service,fsharp/fsharp,Heather/fsharp,eloraiby/fsharp,0x53A/FSharp.Compiler.Service,alfonsogarciacaro/FSharp.Compiler.Service,BillHally/FSharp.Compiler.Service,ncave/FSharp.Compiler.Service,sergey-tihon/FSharp.Compiler.Service,dsyme/fsharp,dsyme/FSharp.Compiler.Service,vasily-kirichenko/FSharp.Compiler.Service,dsyme/fsharp,brettfo/visualfsharp,wk-j/fsharp,fsharp/fsharp,matthid/FSharp.Compiler.Service,dsyme/fsharp,sergey-tihon/FSharp.Compiler.Service,brettfo/visualfsharp,alfonsogarciacaro/FSharp.Compiler.Service,mafiya69/fsharp,In2TheWild/fsharp,rneatherway/FSharp.Compiler.Service,0x53A/FSharp.Compiler.Service,BillHally/FSharp.Compiler.Service,Jand42/FSharp.Compiler.Service,dsyme/fsharp,brettfo/visualfsharp,vasily-kirichenko/FSharp.Compiler.Service,syeerzy/visualfsharp,In2TheWild/fsharp,fsharp/fsharp,eloraiby/fsharp,syeerzy/visualfsharp,dsyme/fsharp,rojepp/FSharp.Compiler.Service,brettfo/visualfsharp