Added WebDAV status codes

There are WebDAV methods exists but status codes are not. Added codes from http://www.webdav.org/specs/rfc4918.html#status.code.extensions.to.http11
Merge pull request #574 from TrueBers/patch-1

Added WebDAV status codes
Remove debug assertion message.
Don't let an exception hinder HTTP client connections to be closed.
Fix using makeIsolated for creating heap allocated structs.
support multiple To's in sendMail
add support for CC's and BCC's in sendMail
fix imports - more restrictive import checking in dmd

- missing imports due to qualified usage

- missing selective import

- selective imports from wrong module
Merge pull request #584 from MartinNowak/fixImports

fix imports - more restrictive import checking in dmd
Merge pull request #582 from Extrawurst/patch-1

support multiple To's in sendMail
Add support for comma separated recipients in sendMail. See #582.
Fix comma separated recipients.
Add SSL support to mongo driver
Advertise SSL support and mention nonstandard 'sslverifycertificate'
Merge pull request #587 from gittywithexcitement/master

Add SSL support to mongo driver. Fixes #575.
Let listenHTTP fail if listening fails for all bind addresses. Fixes #580.
Make all overloads of listenHTTPPlain private.
Add the possibility to disable command line processing.

Use -version=VibeDisableCommandLineParsing for this.
Update change log.
Add summaries for all versions in the change log.