Add ssh_config.GetCanonicalCase to print correct key case

[StephenBrown2]

Adds canonical casing to print output, using the GetCanonicalCase func added in PRs to ssh_config

Example:

Host ssh.github.com gist.github.com github.com github
    Hostname ssh.github.com
    IdentitiesOnly yes
    IdentityFile ~/.ssh/id_ed25519
    User git

gets displayed appropriately as:

	gist.github.com(~/.ssh/config) -> git@ssh.github.com:22
	    IdentitiesOnly = yes
	    IdentityFile = ~/.ssh/id_ed25519

	github(~/.ssh/config) -> git@ssh.github.com:22
	    IdentitiesOnly = yes
	    IdentityFile = ~/.ssh/id_ed25519

	github.com(~/.ssh/config) -> git@ssh.github.com:22
	    IdentitiesOnly = yes
	    IdentityFile = ~/.ssh/id_ed25519

	github.me(~/.ssh/config) -> git@ssh.github.com:22
	    IdentitiesOnly = yes
	    IdentityFile = ~/.ssh/id_ed25519

	ssh.github.com(~/.ssh/config) -> git@ssh.github.com:22
	    IdentitiesOnly = yes
	    IdentityFile = ~/.ssh/id_ed25519

TODO: Remove reference to github.com/StephenBrown2/ssh_config when kevinburke/ssh_config#39 or xwjdsh/ssh_config#1 get merged

[xwjdsh]

Thank you for your contribution.

[xwjdsh]

Included in v0.5.3.