Relative path issues with fake script compilation to .fake folder.

[uladz-zubrycki]

Not sure, If it's a problem of fake or mine but nevertheless.
Suppose we've got next directories structure
$/
    .nuget/
    packages/
        Fake/
    cmd/
        run.cmd
    fsx/
        run.fsx

Where run.cmd is a fake script bootstrapper, which downloads fake to the packages folder with use of .nuget/nuget.exe and starts ../fsx/run.fsx then.
And run.fsx has next content

#I @"../packages/" 
#r @"FAKE/tools/FakeLib.dll"

open Fake
open System.IO
Directory.SetCurrentDirectory (__SOURCE_DIRECTORY__)

Target "Default" (fun _ -> 
     trace "Running default target"
)

RunTargetOrDefault "Default"

After executing the script, empty folder .fake will be created inside cmd folder, while compilated FSI-ASSEMBLY.dll will be saved inside fsx one. Also, after all the targets will be completed successfully, we will getSystem.IO.DirectoryNotFoundException inside Fake.FSIHelper.runFAKEScriptWithFsiArgsAndREdirectMessages at FSIHelper.fs#340

Everything will be ok without Directory.SetCurrentDirectrory(__SOURCE_DIRECTORY__), but I want all the pathes used in script to be relative to the fsx files itself and not the cmd bootstrapper.