Initial changes for build preview.
Port Changeset 1209363 to BuildPreview (Compiler Package Changes to support open source build.) (changeset 1210286)
Port Changeset 1209382 to BuildPreview (Enable OpenSource Builders to debug their creations) (changeset 1210350)
Fix for Bug #905496 by adding a check for AutoProps before checking for initializers. (changeset 1210987)
Changes to diagnostic analyzer API based on API review (changeset 1211052)
Porting changeset 1209154 to build preview branch

Removing unused solution configurations from Roslyn.sln. (changeset 1211259)
Porting changeset 1209160 to build preview branch

Removing duplicate entries from repositories.config (changeset 1211262)
Porting changeset 1209320 to build preview branch:

Removing duplicate entries from repositories.config (changeset 1211406)
Porting changeset 1209326 to build preview branch:

If a workspace indicates that there are DocumentIds associated with a text container, then there should always be a current context DocumentId for that container. Therefore, when a document is opened in the Workspace, it should be set as the current context document for its text container if the 'isCurrentContext' flag is set or if there exists no current context document for that container. This change adds the latter condition and asserts if this state is out of sync when a feature attempts to get the active context document for a text container.

Additionally, the DocumentProvider check for whether a document key is in the current context is now correct in cases where multiple projects map to the same hierarchy. (changeset 1211435)
Porting changeset 1209431 to build preview branch:

fixed smart indentation for lambda

calculated indentation incorrectly for one of indent block option. (changeset 1211452)
Porting changeset 1209457 to build preview branch:

Avoid a race condition running the Syntax Generator

I haven't quite determined _what_ is preventing the xsd from being read during a VS "Rebuild" operation, but let's avoid the whole mess by not copying the file to the output directory and loading it from disk at all. (changeset 1211472)
Porting changeset 1209571 to build preview branch:

Sorting project items. (changeset 1211485)
Porting changeset 1209599 to build preview branch:

Fixing spelling here and there. (changeset 1211498)
Port changeset 1210613 to build preview branch:

The open source build has CompilerPackage project and CompilerPackageFiles project both of which generate CompilerPackage.dll.  This check in fixes that by renaming CompilerPackages dll to CompilerPackageVSIX.dll (changeset 1211513)
Port changeset 1210341 to build preview branch

Fix commandline unit tests. (changeset 1211519)
Port changeset 1210991 to build preview branch:

     Implements EnC support for VB array-initialized fields (e.g. Dim a(10) As Integer).
     Fixes various issues around fields with shared initializers (e.g. Dim a,b As New C()) and auto-properties with AsNew clause (e.g. Property P As New C()).

     Makes breakpoint spans (IDE) consistent with sequence points (compiler) and makes sequence points for various forms of field and property initializers also more consistent with each other.
     Specifically:

     before:                                                                                  after:
     <A>Dim [|F As Integer = 1|]                                              <A>Dim [|F As Integer = 1|]                                         (no change)
     [|<A>Property P As Integer = 1 Implements I.P|]           <A>Property [|P As Integer = 1|] Implements I.P     (changed to match fields)

     Dim [|F|], [|G|] As Integer = 1                                              Dim [|F|], [|G|] As Integer = 1                                       (no change)
     Dim [|F(1), G(1) As Integer|]                                                Dim [|F(1)|], [|G(1)|] As Integer                                    (change to match fields with shared AsNew clause)
 (changeset 1211523)
Merge changeset 1211284 to the build preview branch:

Ensure that prepare.bat Enables the roslyn packages.
Ensure that when building roslyn we delete tthe vssqmmulti.dll (sqm logging) so that OSS builds do not provide innacurate logging. (changeset 1211531)
Merge changeset 1211431 to the build preview branch:

Update System.Collections.Immutable 1.1.18 -> 1.1.20
Update System.Reflection.Metadata 1.0.8 -> 1.0.9 (changeset 1211547)
Merge changeset 1211545 to build preview branch:

Change the RootSuffix extensions are deployed to from RoslynDev to Roslyn (changeset 1211548)
Merge changeset 1211413 to build preview branch:

Adjusts sequence points of array-initialized local variable declarations to match field declarations.

     Before -> after
     Dim [|F(1), G(1) As Integer|]  ->  Dim [|F(1)|], [|G(1)|] As Integer
 (changeset 1211563)