Added [SecurityCritical] to the exception class methods. Knagis#48

Updated version to 0.9.1

Updated release notes

Increased nuget package version.

Increased version number

Increased nuget version number

Increased nuget version since 0.8.1 was published with incorrect bina…

…ries. Also .NET Core project had lost the setting to create .dll file.

Updated version for nuget.

Fixed .dll path

Increased to 0.7 version which is more correct since the public API h…

…as been expanded.