import remaining FCS code (dotnet#2951)

* import remaining FCS code

* add missing files

* fix some parts of build

* more FCS integration work

* build fcs.dll and vs targets

* revert changes to proj files

* update sig files

* various cleanup items

* simplify #ifs

* fix various tests

* enable scripting testing

* fix build

* fix build

* fix tests and build

* fix tests and build

* fix build

* fix tests

* fix tests

* add diagnostic and fix coreclr build

* fix printing tests

* test updates

* improve error logging

* integrate visualfsharp master

* dependency files

* proj file

* dependency files

* fix build

* fix fsi.exe in GUI mode

* add end of line to source text if needed as before

* fix many tests

* fix remaining tests

* better strong name logic to fix final test

* reinstate all strong names

* fix last tests

* fix last test again

Author: dsyme

FSharp.Editor.fsproj

@@ -4,7 +4,7 @@
   <PropertyGroup>
     <FSharpSourcesRoot>$(MSBuildProjectDirectory)\..\..\..\src</FSharpSourcesRoot>
     <ProjectLanguage>FSharp</ProjectLanguage>
-    <SIGN_WITH_MSFT_KEY>true</SIGN_WITH_MSFT_KEY>
+    <UseVsMicroBuildAssemblyVersion>true</UseVsMicroBuildAssemblyVersion>
   </PropertyGroup>
   <Import Project="$(FSharpSourcesRoot)\FSharpSource.settings.targets" />
   <PropertyGroup>