Launchpad ingestion to archive endpoint

Wire up launchpad ingestion to charmstore filling out new api/models.
add missing lpad to dependencies.tsv
Work around bug in go 1.2.1

Go 1.2.1 has a bug requiring Content-Type to be sent.
Since we are posting to a go server which may be running on 1.2.1, we
should send the Content-Type header.

https://code.google.com/p/go/source/detail?r=a768c0592b88
use camelCase consistently
add logging-config example
s/unwanted/sunsupported/
remove noop goto

I copied code from _old/branch.go and deleted things which did not make
sense, turning the goto into a no-op. In fact, after making sure that
the code is not necessary, I'm not convinced it ever prevented the race
condition which it intended to prevent.
Do closes body

trace log output the branch directory
update gopkg.in/juju/charm.v3 dependency
change logger name; comment load function
refactor addPromulgatedCharmURLs

Comment on use of OfficialSeries for Promulgated.
Removed an empty line.
deindent needless !error block
remove needless local
handle NewRequest error

The url could be bad.
Clean up - addressing review comments

Use -u for auth parameter to be consistent with curl
SimpleWriter to os.Stderr is the default writer. Remove it if not
showing the log.
Clean up many log formatters and levels.
Assign URLs to result of addPromulgatedCharmURLs. Remember that slices
are values not pointers.
use a temp file for each charm upload

Upload each url (was missing ~charmers paths without this)
Merge pull request #95 from jrwren/launchpad-ingestion

Launchpad ingestion to archive endpoint

Wire up launchpad ingestion to charmstore filling out new api/models.
internal/v4: implement changes/published
internal/v4: add changesPublished error tests; disallow limit=0
Merge pull request #104 from rogpeppe/045-changes-published

internal/v4: implement changes/published

As recently added to the specification.