Recovery release for 1.x

• #273 - Added .Net Standard 2.0 target framework for vNext contributed by Manuel Cabral (Manny651)
• #269 - Some typos contributed by (cortex93)
• #257 - Error in BusClientFactory.CreateDefault() on net core 2.0
• #233 - fix typo in NamingConventions.RetryLaterExchangeConvention contributed by Bohdan Sachkovskyi (sachokFoX)
• #231 - Fix typo in spelling Dependency contributed by Serhii Almazov (almazik)