Fix #144: blocking project file (#179)
Fix #144: blocking project file (#179)

* Minor: fix warning.

* Fixed: "Cann't open project file because it's been used by another process".

ncave/Fable,mastoj/Fable,inosik/Fable,fable-compiler/Fable,inosik/Fable,ncave/Fable,fable-compiler/Fable,mastoj/Fable,mastoj/Fable,markek/Fable,fable-compiler/Fable,ncave/Fable,ncave/Fable,fable-compiler/Fable,ncave/Fable,markek/Fable,fable-compiler/Fable,markek/Fable,ncave/Fable,ncave/Fable,fable-compiler/Fable,fable-compiler/Fable