Use commit-specific hash for port permalinks

[JavierMatosD]

This uses "master" instead of a commit hash. This will make the update PRs much smaller since the majority of the changes are just updating the commit in the url.

[JavierMatosD]

This change substantially increases the website rebuild time since into runs two separate git operations for every port in the registry - git log and git rev-list.

This is redundant. I'm going to refactor to use one command and extract both pieces of information. Still slow, but better than current implementation.

Update: now we are capturing both pieces of info, date modified and commit, in one git command. It's still slow but it's similar to what it was before.