Added more parameterizations
normalize fail message format

Use angle brackets around <$param> in message to make it clear when a
variable is blank.
Merge pull request #30 from ghoneycutt/add_more_params

Add more params
Add feature to allow setting 'SendEnv XMODIFIERS'

This defaults to false and has options to independently set this in both
ssh_config and sshd_config.
Merge pull request #31 from ghoneycutt/add_sendenv_xmodifiers

Add feature to allow setting 'SendEnv XMODIFIERS'
Release v2.5.0

Ability to manage more options in the ssh_config and sshd_config files.

ssh_config
* SendEnv XMODIFIERS

sshd_config
* SendEnv XMODIFIERS
* PasswordAuthentication
* AllowTcpForwarding
* X11Forwarding
* UsePAM
* ClientAliveInterval