Improves location used for base interface errors when partial classes are used

Apply non-printable escaping to characters

Use Enumerable.Repeat and code cleanup

Remove synchronous method.

Make more of the IDE layer async.

Ask dotnetbot to kick off vsi tests

Also include a 'git fetch upstream' step for the people doing
merges.  This is useful if they aren't already up to date.

Fixed app.config casing

don't show `(Awaitable)` for dynamic objects

use predefined type keywords if the real types would only be bracketed

e.g., always prefer `String` to `[String]` in VB

...by adding or removing ObjectDisplayOptions.EscapeNonPrintableCharacters
as appropriate.

Ensured that all uses of app.config in our product / test code base is
used in the lower case form.  This helps with our Unix efforts where
mixing the case can be significant.  Updated all of the project
references to ensure they used the lower case version as well.

removed unused usings

added callstack to AD0001 and added reg key that will crash VS instea…

add one more entry to InvalidDiagnosticLocationReported to show diagn…

Make all internal nodes of IOperation tree subtypes of IOperation

Improves location used for base class errors when partial classes are used

Fix case where we weren't realizing tabs were used for indentation in broken code.

Fixes #4014

Unify FindTokenOnLeftOfPosition and FindTokenOnRightOfPosition helpers

ISymUnmanagedWriter cleanup

Fix another typo in the makefile

Merge TopLevel and MethodBody speculative models

Fail tests on failed assert

Improved SyntaxFactory for documentation comments (Issue #218)