Show zsh version on CI build
Install zsh in the install phase.
Add zsh 5 PPA for testing
Fix PPA checking
Reorganize Travis-CI file

Make the steps appear in the order they are executed
Fix grammar
Rename Travis-CI PPA file to be more descriptive.
Merge branch 'patch-1' of github.com:GUIpsp/antigen into patch-1

Conflicts:
	.travis.yml
Merge pull request #61 from GUIpsp/patch-1

Add zsh 5 to the Travis-CI build matrix.