added unit tests for all loglevels and for static log fluent builder
added unit tests for all loglevels and for static log fluent builder

breyed/NLog,tohosnet/NLog,nazim9214/NLog,UgurAldanmaz/NLog,AndreGleichner/NLog,UgurAldanmaz/NLog,ilya-g/NLog,Niklas-Peter/NLog,bryjamus/NLog,bjornbouetsmith/NLog,sean-gilliam/NLog,NLog/NLog,bhaeussermann/NLog,tetrodoxin/NLog,bryjamus/NLog,pwelter34/NLog,hubo0831/NLog,BrutalCode/NLog,kevindaub/NLog,MoaidHathot/NLog,MoaidHathot/NLog,tohosnet/NLog,michaeljbaird/NLog,michaeljbaird/NLog,FeodorFitsner/NLog,littlesmilelove/NLog,ie-zero/NLog,luigiberrettini/NLog,Niklas-Peter/NLog,luigiberrettini/NLog,AndreGleichner/NLog,hubo0831/NLog,breyed/NLog,ArsenShnurkov/NLog,littlesmilelove/NLog,bjornbouetsmith/NLog,304NotModified/NLog,MartinTherriault/NLog,BrutalCode/NLog,snakefoot/NLog,kevindaub/NLog,bhaeussermann/NLog,FeodorFitsner/NLog,tetrodoxin/NLog,ie-zero/NLog,pwelter34/NLog,ilya-g/NLog,nazim9214/NLog,MartinTherriault/NLog,ArsenShnurkov/NLog