Ignore DB specific tests which rely on PostgreSQL

[Almantask]

public class IgnoreOnMonoFactAttribute : FactAttribute {

    public IgnoreOnMonoFactAttribute() {
        if(IsRunningOnMono()) {
            Skip = "Ignored on Mono";
        }
    }
    /// <summary>
    /// Determine if runtime is Mono.
    /// Taken from http://stackoverflow.com/questions/721161
    /// </summary>
    /// <returns>True if being executed in Mono, false otherwise.</returns>
    public static bool IsRunningOnMono() {
        return Type.GetType("Mono.Runtime") != null;
    }
}