Add new env. variables and options
- HTTP_BASE_URL to control URL prefix, defaults to /
- HTTP_SSL_TERMINATED to explicitly set if Corteza is running behind HTTPS
Refresh and document webapp/Makefile with more dev tasks
Fix all absolute URLs in applications, logos, icons
Improve logic behind integrated webapp serving, inject/replace <base href> tag according to URL prefix
Prevent mounting api & webapps to the same base
