Refactor BlockingBufferManager.

Remove StyleCop rules regarding file headers, so file headers can
consist of two simple lines that specify the license name.

Limit code lines to 100 characters.

Apply the changes starting with BlockingBufferManager.cs.
Refactor rest of the Dawn.SocketAwaitable project.

Refactor all the code files in the project so they would comply with the
updated StyleCop rules.

Limit code lines to 100 characters in every code file in the project.

Remove trailing blanks from the project file and all the code files.