Fixed https_middleware that was setting url_scheme to https always.
fixed https middleware in coverstore-server.
Fixed recaptcha on https.

Using protocol relative URL for recaptcha.
Fixed the URLs when accessing covers.openlibrary.org internally.

When we switched to protocol-relative URLs the uploads broke. Fixed it
by adding http: prefix to them if the URL starts with //.
Don't fail when when parsing blog feeds fail.