Since HTTPS is "the new normal", this update changes a lot of man page
examples to use https://example.com instead of the previous "http://..."
Closes#5969
This change introduces new alternatives for the existing six
curl_easy_getinfo() options that return sizes or speeds as doubles. The
new versions are named like the old ones but with an appended '_T':
CURLINFO_CONTENT_LENGTH_DOWNLOAD_T
CURLINFO_CONTENT_LENGTH_UPLOAD_T
CURLINFO_SIZE_DOWNLOAD_T
CURLINFO_SIZE_UPLOAD_T
CURLINFO_SPEED_DOWNLOAD_T
CURLINFO_SPEED_UPLOAD_T
Closes#1511
