[NuGet] Check ProjectTypeGuids are read from project.

When installing a NuGet package the project's ProjectTypeGuid is used
to determine if a project is a web project. This determines whether
the web.config or app.config is affected by any transforms included
in the NuGet package.
bumped debugger-libs
[Debugger] Nuke the debugger engine priority list (and UI)
Merge pull request #536 from MatthewDiamond/patch-1

[Ide] Fix for resx generator resource locating
Merge pull request #551 from DavidKarlas/pdbLocking

[CorDebugger] Pdb locking and DebuggerSession memory leak
New base class for debugger engine implementations

Debugger engines now have to subclass DebuggerEngineBackend.
The old IDebuggerEngine interface is still supported, but it is now marked as
obsolete.
Use the new base class for debugger engines
Bump md-addins
[Ide] Reference System.Windows.Forms for ResXResourceReader

We already pulled it in transitively anyway.
bumped debugger-libs
[Debugger] disable a bunch of tests for older mono versions
fixed the build
[Core] Remove duplicate CredentialStore singleton
[Mac] Handle keychain persistence in MacProxyCredentialProvider
[Mac] Don't make duplicate/concurrent credential prompts
[Mac] Read system proxy credentials

Fixes BXC 19828 - User is prompted to re-enter proxy credentials
in XS, while credentials are already entered in system preferences
on Mac
[TextEditor] Fixed reserved keyowords in F# language.
Fixed 'Bug 19811 - F# reserved OCAML token asr fails to highlight'
Fixed 'Bug 19812 - F# reserved OCAML token land fails to highlight'
Fixed 'Bug 19813 - F# reserved OCAML token lor fails to highlight'
Fixed 'Bug 19814 - F# reserved OCAML token lsl fails to highlight'
Fixed 'Bug 19815 - F# reserved OCAML token lsr fails to highlight'
Fixed 'Bug 19816 - F# reserved OCAML token lxor fails to highlight'
Fixed 'Bug 19817 - F# reserved OCAML token mod fails to highlight'
[TextEditor] Fixes some F# highlighting issues.
Fixed 'Bug 19809 - F# not keyword fails to highlight'
Fixed 'Bug 19810 - F# select keyword fails to highlight'
Fixed 'Bug 19808 - F# let keyword highlights only after entering a
space after word'
Also fixed issues with keywords that ended with '!'. From the
highlighting perspective F# is a complex language.
[NuGet] Add tests for BackgroundPackageActionRunner.
Immediate window CodeCompletion appeared above typing text fixing Bug 14578