yum.conf.sample: Add example yum.conf

This uses the local yum.repos.d and sets the releasever=7 needed
for running on a non-yum based machine.

Story: 2003764
Task: 26454

Change-Id: Id616eef24d66fd43d4ab0d7356c1eafba3c84af2
Signed-off-by: Saul Wold <sgw@linux.intel.com>

centos-mirror-tools/yum.conf.sample

@@ -0,0 +1,42 @@
+[main]
+releasever=7
+cachedir=/tmp/cache/yum/$basearch/$releasever
+keepcache=0
+debuglevel=2
+logfile=/tmp/log/yum.log
+exactarch=1
+obsoletes=1
+gpgcheck=1
+plugins=1
+installonly_limit=5
+bugtracker_url=http://bugs.centos.org/set_project.php?project_id=23&ref=http://bugs.centos.org/bug_report_page.php?category=yum
+distroverpkg=centos-release
+override_install_langs=en_US.utf8
+tsflags=nodocs
+reposdir=yum.repos.d
+
+
+#  This is the default, if you make this bigger yum won't see if the metadata
+# is newer on the remote and so you'll "gain" the bandwidth of not having to
+# download the new metadata and "pay" for it by yum not having correct
+# information.
+#  It is esp. important, to have correct metadata, for distributions like
+# Fedora which don't keep old packages around. If you don't like this checking
+# interupting your command line usage, it's much better to have something
+# manually check the metadata once an hour (yum-updatesd will do this).
+# metadata_expire=90m
+
+# PUT YOUR REPOS HERE OR IN separate files named file.repo
+# in /etc/yum.repos.d
+#####
+# CentOS-Base.repo
+#
+# The mirror system uses the connecting IP address of the client and the
+# update status of each mirror to pick mirrors that are updated to and
+# geographically close to the client.  You should use this for CentOS updates
+# unless you are manually picking other mirrors.
+#
+# If the mirrorlist= does not work for you, as a fall back you can try the
+# remarked out baseurl= line instead.
+#
+#