Bring remaining System.Diagnostics.* members to netstandard2.0

[AlexGhiondea]

This is a grab bag of a couple of APIs that don't fit well in other issues:

P:System.Diagnostics.ProcessStartInfo.EnvironmentVariables
P:System.Diagnostics.ProcessStartInfo.ErrorDialog
P:System.Diagnostics.ProcessStartInfo.ErrorDialogParentHandle
P:System.Diagnostics.ProcessStartInfo.Password
P:System.Diagnostics.ProcessStartInfo.Verb
P:System.Diagnostics.ProcessStartInfo.Verbs
P:System.Diagnostics.ProcessStartInfo.WindowStyle
F:System.Diagnostics.SourceLevels.ActivityTracing
M:System.Diagnostics.StackTrace.GetFrame(System.Int32)
P:System.Diagnostics.Switch.Attributes
M:System.Diagnostics.Switch.GetSupportedAttributes