added optional ignore_md5_mismatch parameter
changed ignore_md5_mismatch to validate_md5
Support using paramiko to set up accelerate connection

Adds original_transport attribute to Runner to track what the original
transport was before it is changed to 'accelerate'.
If using paramiko in original_transport, uses ParamikoConnection.  If
not, falls back to SSHConnection like before.
Expand tilde in paths in file module
Added remote_user to plays

Still compatible with user: but deprecating it so we can have
a matching remote_user: in tasks, cannot be user: because of the
module of the same name. #3932

Signed-off-by: Brian Coca <briancoca+dev@gmail.com>
fixed typo
Signed-off-by: Brian Coca <briancoca+dev@gmail.com>
subelements lookup plugin
Locate easy_install path after (optionally) creating virtualenv.

Without this, the first call to the easy_install module with a new virtualenv
will only create the virtualenv without installing the intended package, since
the `_is_package_installed` check will succeed as running /usr/bin/easy_install
as non-root user will return permission denied error with empty stdout.
Use low-level package objects in the apt module to check installed state

Packages which are half-installed are not adequately represented by
the .is_installed field of the apt.package.Package object. By using the
lower-level apt_pkg.Package object (which provides the .current_state
field), we can check for a partially-installed state more accurately.

Fixes #3421
When checking conditionals, don't dereference when the variable contains dashes

Fixes #4104
Update releases.txt
Update 1.4 specfile -- no need for node fireball package, release dates
Update Debian changelog for 1.4 builds.
Adding sshpass as packaging requirement and fixing VERSION
Update CONTRIBUTING.md
Update CONTRIBUTING.md

Add URLs to mailing lists instead so it's obvious on how to subscribe
Update CONTRIBUTING.md

Github formatting fixups
Update CONTRIBUTING.md

URL formatting
Update CONTRIBUTING.md

Convert URLs to short form hyperlinks
Update CONTRIBUTING.md

word wrap and formatting