Update metadata cache for upstream's eclass changes
Mark EAPI 0-3 as banned in the repository

This has been the case for a long time now, but repoman supports testing this
without relying on the push hook now.
Mark EAPI 4 as deprecated in this repository

EAPI 4 is not in direct use in this repository now, but repoman breaks in
strange ways when the repos are merged when using the AST leafs which contain
EAPI 4 ebuilds in addition to this.
Moved sphinxcontrib-httpdomain to dev-python

This is full move prior to removal to work around the breakage caused by having
to keep this in ::shadow once it dropped from here.  Refs #795.

Still less work than the alternative, which is a very sorry state of affairs.
[sphinxcontrib-httpdomain] Moved to ::shadow

Closes #795.
Manual update of removal texts
[QA] Fix headings in removals doc
Merge branch 'feat/removals'

* feat/removals:
  Manual update of removal texts
  [sphinxcontrib-httpdomain] Moved to ::shadow
  Moved sphinxcontrib-httpdomain to dev-python