Refactoring
This release contains major refactoring of the code, to allow for some new features. One of the major changes is that the code is more modular, to allow for e.g. Azure Certificate Service to be used together with Azure Key Vault (not included in this release).
I also removed the tight dependency to the local file system of the web server, so that the extension now can run on another site, than the one the certificate is installed on (this will allow a separate release that for functions instead of relying on web jobs, and it makes local debugging easier). This change however, changes how the acme challenge file is place on the web server, as the KUDU file API now is used. This might have unforeseen consequences for those who have used their own letsencrypt:WebRootPath please let me know if that causes problems.
Finally the release contains a breaking change, if you relied on the first run of the web job to setup your hostname binding, then you are out of luck, as I removed that part of the code, as it doesn't really belong in this site extension, now that it is supported to set hostname bindings using ARM templates.
This release took longer than expected, as I encountered a few problems with the official nuget Microsoft.Azure.Management.WebSites and had to just use the ARM API manually.