docs: fix Makefile ordering for build

The documentation directory needs to come after Common, since the docs
build depends on Common/bkr/__init__.py existing.

This feels quite relevant right now...
http://miller.emu.id.au/pmiller/books/rmch/

Change-Id: Ieee47798c78c8fe222f8f3afa08356847eff14ec
add beaker-sync-tasks to %files

Change-Id: I1c96dbc811eac7a558d8e356063d571cbcbdc300