Add the rake "lint" target, and fix resulting minor errors, which were:
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manifests/mod/python.pp - WARNING: class not documented on line 1
manifests/mod/wsgi.pp - WARNING: class not documented on line 1
manifests/vhost.pp - WARNING: variable not enclosed in {} on line 80
manifests/vhost.pp - WARNING: variable not enclosed in {} on line 82
manifests/vhost/redirect.pp - WARNING: variable not enclosed in {} on line 43
manifests/vhost/redirect.pp - WARNING: variable not enclosed in {} on line 45
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Change-Id: I2213f314d4bf92b4ddf58dbb19a80783380a55ce
482441c9af