Cake.Core 0.5.5

Added alias to retrieve all environment variables. Added additional xUnit settings. Added verbose message when glob pattern did not match anything. Added task setup/teardown functionality. Fix for referencing parent directory in glob patterns. Added verbose logging for file and directory aliases. Removed quotes from MSBuild arguments. Added StartProcess alias overload taking process arguments as string. Added Cake.Testing NuGet package. Added support for AssemblyConfiguration when patching assembly information. Fixed bug with dots in glob patterns. Fixed bug with reference loading (affects #tool and #addin directives).