Configuration.md: format for editor readability

Most lines are now limited to 79 characters. This makes the document
much easier to read in a mortal text editor.
Configuration.md: make hyperlink relative

It was pointing to a specific branch, which isn't even the "main" dev
branch anymore.
Configuration.md: add more detail to pipeline conf

1) The suggested names for zerocloud middleware filters now are prefixed
with "zerocloud-", for disambiguation.
2) There are now detailed instructions for where the zerocloud filters
need to be placed in the "pipeline:main" configuration.
Configuration.md: add job chain config doc
Merge pull request #173 from larsbutler/update-configuration-doc

Update configuration documentation
acls
proxyquery: add a bunch job authorization comments
test_proxyquery: clean up bad imports in test apps
test_proxyquery: fix test breakage from a rebase
proxyquery: fix the sequence of path_info change

The refactoring of post_job and some rebases put a req.path_info value
change out of order, and some tests were breaking. All tests pass now.
proxyquery: fix source handling for api chain