Documentation URLs should not include CiviCRM version info

Summary

In CiviCRM 4.6, several places in the UI point users to incorrect URLs for documentation pages. These URLs are incorrect because they have current in the URL and should not. The URL should not have current in it because (a) this is the 4.6 branch, and (b) the version shouldn’t be specified for each URL since the docURL function handles that.

Steps to reproduce

Here is one example of this (but there are several others too):

1. Begin with a 4.6 installation (this bug doens’t affect 4.7)
2. Go to the Scheduled Reminders page /civicrm/admin/scheduleReminders?reset=1
3. Copy the documentation link in the help text at the top of the page.
4. Expect this link to be https://docs.civicrm.org/user/en/4.6/email/scheduled-reminders
5. Observe this link to be https://docs.civicrm.org/user/en/4.6/current/email/scheduled-reminders. (Note 4.6/current instead of 4.6)
6. Load the link in your browser.
7. Expect to arrive at a docs page.
8. Observe a redirection error.

Note: the documentation publisher really should be giving a 404 error for a request like this, but docs-publisher has an issue with handling redirection, unrelated to this ticket.