Checks an additional variable named versionedurl for the version name,
and uses the value as the url to reference. If the versionedurl doesn't
contain an entry for the version the current path is used.
e.g.
versionedurl:
v1.8: /docs/home
v1.7: /docs/old-path-to-doc
* Show current version of docs in nav
* Branch in edit link
* WIP version selector
* An actual working but not pretty version dropdown
* update URLs for versions
v1.7: https://kubernetes.io/docs/home/
v1.6: https://v1-6.docs.kubernetes.io/docs/home/
v1.5: https://v1-5.docs.kubernetes.io/docs/home/
v1.4: https://v1-4.docs.kubernetes.io/docs/home/
* fix v1.4 and v1.5 paths
* Tidier drop downs
* Make font visible always
* Make background match main nav always
* change to major.minor version number
* show only major.minor version in drop down list
* switch from githubbranch to docsbranch
* update githubbranch
* update githubbranch values
* Border radius for bottom of dropdown
* Tabs are hard