Ignore InvalidDataException when downloading HTTP content.

This exception can be thrown for invalid gzip data returned by the server.
Use local Logos.Utility in a Debug build.
Upgrade Logos.Utility to 2.0.0.
Log more error information when web requests fail.
Update assembly version.

Includes: better error logging, dependency on new Logos.Utility.
Update assembly version to 0.4.1.

Fixes missing Logos.Utility dependency in v0.4.0 NuGet package.
Ignore generated nupkg files anywhere in repo.
Add build script to create the NuGet package.