What steps will reproduce the problem?
1. Set up Mercurial to serve a repo over ssh 
2. Attempt to use "go get" to access the repo, specifying the repo using an
absolute path

What is the expected output?
I would expect it to be possible

===

I would like to be able to fetch private repositories with "go get", via ssh. 
However, HG over ssh uses a double slash to specify an absolute path, and "go
get" cleans the URL of double slashes, converting them to single slashes. 

Example

A mercurial command to clone the repo would be: 
$ hg clone ssh://myhg.com//abs/path/to/repo"

Attempting it with "go get":
$ go get -x -v myhg.com//abs/path/to/repo.hg

Results in:
...
# cd .; hg identify ssh://myhg.com/abs/path/to/repo
remote: abort: There is no Mercurial repository here (.hg not found)!
abort: no suitable response from remote hg!
myhg.com/abs/path/to/repo.hg (download)

HG uses a double slash to denote an absolute path.  With a single slash, the path is
taken relative to the user's home directory (which is not appropriate for shared repos). 

===

Kyle Lemons had some notes:
- to handle this case, only // between the host and path would need to be maintained
- we might also only allow the // when we try ssh://, since that seems like the only one
that wants it