EnqueueTimeoutMilliseconds set to 90 milliseconds
performance: workers count set to max between 2 or processors count / 2
usability: Cancelling previous task info show to the user
for instead of foreach to eliminate local var not used
cosmetics: unused using removed
fixes #49 F5 works now
Message about creating rtf page added
usability: the message about pending messages parsing added
usability: calculating time to parse pending messages displayed to the user.
finish loading message shortened
refactoring: Special method that runs plain query and returns scalar result added into DB connection class
refactoring: a couple of warnings eliminated about implicit closures.
default page size set to 2000
cosmetics: obsolete code removed
fixes #50 application hang on cancel reading fixed
don't add message to cache if cancel in progress
refactoring: renaming method paremeter to improve readability
refactoring: ExecuteNonQuery method with action before run introduced.
one more hang on quit fixed
fixes #51 application site link added into About dialog