Update Changelog.md to fix broken links
Update Changelog.md to fix broken links

* This returned a 404, https://github.com/chef-cookbooks/jenkins/tree/5.0.0
* This does a compare, but needs to have the `v` prefix applied to `5.0.0`

Signed-off-by: Gregory Kman <99ace95f3cd6b1aeac0956ce08f86164312c161c@gmail.com>

b-dean/jenkins,gshively11/jenkins,daften/cookbook-jenkins,dshvedchenko/jenkins,opscode-cookbooks/jenkins,samdunne/jenkins,Dispader/jenkins,gshively11/jenkins,chef-cookbooks/jenkins,daften/cookbook-jenkins,Dispader/jenkins,chef-cookbooks/jenkins,b-dean/jenkins,Dispader/jenkins,juliandunn/jenkins,dshvedchenko/jenkins,opscode-cookbooks/jenkins,b-dean/jenkins,juliandunn/jenkins,chef-cookbooks/jenkins,daften/cookbook-jenkins,opscode-cookbooks/jenkins,samdunne/jenkins,dshvedchenko/jenkins,juliandunn/jenkins,samdunne/jenkins,gshively11/jenkins