Replace godep with vndr

Vndr has a simpler configuration and allows pointing to forked
packages. Additionally other docker projects are now using
vndr making vendoring in distribution more consistent.

Updates letsencrypt to use fork.
No longer uses sub-vendored packages.

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

vendor/github.com/ncw/swift/notes.txt

@@ -1,55 +0,0 @@
-Notes on Go Swift
-=================
-
-Make a builder style interface like the Google Go APIs?  Advantages
-are that it is easy to add named methods to the service object to do
-specific things.  Slightly less efficient.  Not sure about how to
-return extra stuff though - in an object?
-
-Make a container struct so these could be methods on it?
-
-Make noResponse check for 204?
-
-Make storage public so it can be extended easily?
-
-Rename to go-swift to match user agent string?
-
-Reconnect on auth error - 401 when token expires isn't tested
-
-Make more api compatible with python cloudfiles?
-
-Retry operations on timeout / network errors?
-- also 408 error
-- GET requests only?
-
-Make Connection thread safe - whenever it is changed take a write lock whenever it is read from a read lock
-
-Add extra headers field to Connection (for via etc)
-
-Make errors use an error heirachy then can catch them with a type assertion
-
- Error(...)
- ObjectCorrupted{ Error }
-
-Make a Debug flag in connection for logging stuff
-
-Object If-Match, If-None-Match, If-Modified-Since, If-Unmodified-Since etc
-
-Object range
-
-Object create, update with X-Delete-At or X-Delete-After
-
-Large object support
-- check uploads are less than 5GB in normal mode?
-
-Access control CORS?
-
-Swift client retries and backs off for all types of errors
-
-Implement net error interface?
-
-type Error interface {
-    error
-    Timeout() bool   // Is the error a timeout?
-    Temporary() bool // Is the error temporary?
-}