you can download
absolutely any version from github.
Any release you can find in the "Releases" tab: https://github.com/moodle/moodle/releases
, they one you are after is actually a release of Moodle 3.0 - https://github.com/moodle/moodle/releases/tag/v3.0.0
We don't tag weekly versions but if you want to find a particular weekly version here is how you do it.
Update in version.php is the last commit before the weekly release, so just look for the history of version.php modifications - go to https://github.com/moodle/moodle
, click on version.php , click on History, you will end up on https://github.com/moodle/moodle/commits/master/version.php
From here find the version that you want - it will take a while to browse with the web version but would be faster if you had command line git
Now you can see that on 2015-11-16 there were one commit in 3.0 branch and actually two commits in 3.1 - one was marked as 2015111600.00 and another 2015111600.01 (I think there was a forgotten web service declaration and integrators had to bump version twice).
Now click on the commit on this date and you will see the actual commit diff. Click the button "Browse files" and you will see a snapshot of the Moodle code after this date:
for version 3.0
for version 3.1dev
Press "Clone or download" and then "Download as ZIP". Enjoy