update nuget.exe to latest
target net45 instead of 451 - simplifies csproj & release
update liblog
fix warn on mono
re-target packages to net45
fix travis build
cleanup app.config for samples, samples target latest .net
cleanup owin sample packages
target 4.5.1 in samples so that they work on mono
target 4.5.1 in samples so that they work on mono