fix subprocess external encode issue. https://github.com/mitchellh/vagrant/issues/3706

in io.rb
 subprocess resuts convert external encoding to utf-8

in subprocess.rb
 command line argument convert utf-8 to  external encoding
added conditional for temporary interfaces
favorite SSH client is not limited to PuTTY
Change symbols inside hashes to 1.9 JSON-like syntax
Merge pull request #3880 from cielavenir/document_putty

favorite SSH client is not limited to PuTTY
Merge pull request #3885 from kalmanh/symbols_syntax_19

Change symbols inside hashes to 1.9 JSON-like syntax
hosts/windows: RDP cap shouldn't remove tempfile [GH-3875]
Merge pull request #3874 from gpurkins/sol11-networkfix

guests/solaris11: Added conditional for temporary interfaces
Update CHANGELOG
website/docs: calrify rsync [GH-3872]
providers/docker: support for UDP forwarded ports [GH-3886]
commands/box/add: clarify help text
make box add --help text more accurate

Fixes #3898.
make init --help text more accurate
Merge pull request #3899 from aspiers/help-text

commands/box/add: make --help text slightly more accurate
comamnds/box/add: change help text
drop `-r` flag from `xargs` on OS X

OS X's `xargs` does not support the `-r` flag (which means "do not
execute the command even once if there are no arguments"), but
behaves by default as if it was specified.

You can verify this yourself with this test:

    $ touch zero-length-file
    $ xargs echo <zero-length-file

If `echo` is executed, you will see a blank line.  If it is not
executed (i.e. `-r` is specified or the behavior is implied) then
you will see no blank line.
Merge pull request #3902 from zigg/fix/osx-xargs-r-flag

guests/darwin: drop `-r` flag from `xargs` on OS X
provisioners/puppet: run in elevated mode on Win guests
Merge pull request #3903 from emyl/puppet-elevated

provisioners/puppet: run in elevated mode on Win guests