Fix for U4-5564

If umbracoUseSSL is set to true, change makes GetCurrentServerUmbracoBaseUrl() return HTTPS URL.  Also overrides ApplicationContext.Current.OriginalRequestUrl to use Port 443 instead of originally loaded port.
This revert causes problems if umbracoUseSSL is set to true and the initial request to the instance came via HTTP. As an example, assuming default port 80 for HTTP and umbracoUseSSL is set, this will generate a baseUrl of https://mywebsite:80 which will fail.  If users are using the standard 80 and 443, I don't think they should have to go mucking around with manually specifying the baseUrl for tasks.

Please see 2c212cb16a72314abd4e36616e8787d49e44806f for a solution that I think should automatically handle almost all cases without requiring the task baseUrl to be set.
- If users are running on HTTP 80 or HTTPS 443, they don't need to change anything.
- If users are using non-standard ports but (a) initial request is HTTP and umbracoUseSSL is false or (b) initial request is HTTPS and umbracoUseSSL is true, they don't need to do anything.  Their initial port request will be used as now.
- The only circumstance where users would have to specify the baseUrl is if they are using non-standard ports and there is a mismatch between their initial request protocol and umbracoUseSSL value (i.e., initial request was HTTP, umbracoUseSSL is true, and HTTPS is not on 443).

What do you think?