Update the classes after the addition of the npm fetcher to
match the other fetcher additions.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

The svk fetcher was removed from bitbake 1.22, so svk support should
logically have been removed from oe-core Daisy onwards.

Signed-off-by: Andre McCurdy <armccurdy@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

below is the history on this class. Documentation for newly introduced SOURCE_MIRROR_URL
is already present in oe-core

commit 0ef914b250df46a41348479446214575668943fb
Author: Eric BENARD <eric@eukrea.com>
Date:   Wed Nov 3 13:28:54 2010 +0000

    own-mirrors.bbclass: allow mirroring of scm fetched packages

    this way, it's possible to setup a local webserver (for example
    using busybox httpd -p "8081" -h backuped_download_dir) serving
    a presiously fetched download directory and to build wihout the
    need for an internet access

    this can also be used when connected to know to know which packages
    are missing from the local mirror's directory (and thus are fetched
    from internet as a fallback), it's possible to run the server this way :
    busybox httpd -p "8081" -h backuped_download_dir -vv -f | grep -B 1  response:404
    to get the name of the missing packages.

    Signed-off-by: Eric Bénard <eric@eukrea.com>
    Acked-by: Denys Dmytriyenko <denis@denix.org>
    Acked-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
    Signed-off-by: Tom Rini <tom_rini@mentor.com>

commit 1b661974e3f8f844f6ec4cdb7bb42cef9595b626
Author: Marcin Juszkiewicz <hrw@openembedded.org>
Date:   Sat Mar 10 14:10:06 2007 +0000

    own-mirrors.bbclass: added class which can be used to set PREMIRRORS from config
    - SOURCE_MIRROR_URL is new variable which point to source mirror which will be
      used before fetching from original SRC_URI location.

Signed-off-by: Khem Raj <raj.khem@gmail.com>