Remove SourceLink
Remove SourceLink

Remove SourceLink as it causes the AppVeyor build to fail with the latest version.
Will add back at a later date when OpenCover supports portable PDBs.

martincostello/alexa-london-travel-site,martincostello/alexa-london-travel-site,martincostello/alexa-london-travel-site,martincostello/alexa-london-travel-site