Due to the behavior of URI.parse on Ruby < 2.5 returning the string
value of the parsed URI object may modify the original URL. Specifically
it will remove the `//` prefix characters from SMB paths. When no
host modifications are being made, always return the original value.
Fixes#9636
Always remap old hosts to target host when encountered. When custom
vagrant server is defined, warn when tokens may be attached and allow
time for user to cancel.
Fixes#9442
This fixes GH-6395 by only appending the access_token once. It also fixes a
bug that was never reported. If a user supplied an access_token for a box URL,
Vagrant would silently overwrite it.
After this commit, Vagrant only appends an access_token to the URL if no
value exists at the key.
