skeleton directory for addon and sub domains
Whenever a hosting customer creates a subdomain or addon domain, a plethora of errors appear in the Apache error logs because favicon.ico, robots.txt and 404.shtml do not exist by default. This causes an unnnecessarily large error log file even with custom logging.
Since hosting providers solve this issue for primary domains by using skeleton directories, it is proposed that we use that same skeleton directory for addon and sub domains. This lets hosting providers just solve these problems or go a step further with a "Website coming soon, here's how you upload" page and other brandings they build.
There is no need to have a separate skeleton directory for this, so let's use the same skeleton directory used for that account (the skeleton directory of the reseller/root user that owns that account).
The strong reasoning used for justifying skeleton directories in the first place is being used here for justiifying sekeleton directories for addon domains and subdomains.