Merge pull request #12 from quamotion/fixes/optional-arguments

...Protocol/Chrome/DOMStorage/DomStorageItemsClearedEvent.cs

...romeDevTools/Protocol/Chrome/Database/AddDatabaseEvent.cs

...ols/Protocol/Chrome/Database/ExecuteSQLCommandResponse.cs

...ChromeDevTools/Protocol/Chrome/Debugger/AsyncOperation.cs

.../Protocol/Chrome/Debugger/AsyncOperationCompletedEvent.cs

...ls/Protocol/Chrome/Debugger/AsyncOperationStartedEvent.cs

...Tools/Protocol/Chrome/Debugger/BreakpointResolvedEvent.cs

source/ChromeDevTools/Protocol/Chrome/Debugger/CallFrame.cs

...hromeDevTools/Protocol/Chrome/Debugger/CollectionEntry.cs

...DevTools/Protocol/Chrome/Debugger/CompileScriptCommand.cs

.../Protocol/Chrome/Debugger/CompileScriptCommandResponse.cs

...ols/Protocol/Chrome/Debugger/ContinueToLocationCommand.cs

...s/Protocol/Chrome/Debugger/EnablePromiseTrackerCommand.cs

...ls/Protocol/Chrome/Debugger/EvaluateOnCallFrameCommand.cs

...col/Chrome/Debugger/EvaluateOnCallFrameCommandResponse.cs

...romeDevTools/Protocol/Chrome/Debugger/ExceptionDetails.cs

...hromeDevTools/Protocol/Chrome/Debugger/FunctionDetails.cs

...vTools/Protocol/Chrome/Debugger/GeneratorObjectDetails.cs

...s/Protocol/Chrome/Debugger/GetBacktraceCommandResponse.cs

...evTools/Protocol/Chrome/Debugger/GetPromiseByIdCommand.cs