do not exit after first invalid file

At the moment tools/validate.py exits after it found an
invalid file.

I think it's better to always validate all files and to
exit then if any invalid file was found. This way the
creator of a review request can fix all found issues in
all files and has not to create several patch sets.

Change-Id: Ic5668f0791680802b8cef3b5e1016c9dc76479b9
updated index.html to invite users to join the foundation or take the user survey

Patchset changes Involved to involved, removes (it's free), and indicates
OpenStack Foundation.

Change-Id: Icb18aa3b19f61566b1c0c3d2dfd2a93dd56139a0
generalized highlighting of service cinder-volume

Change-Id: I118cb2ab6080ebbcb1e3bcf5798e2bde4b09fca6
Merge "updated index.html to invite users to join the foundation or take the user survey"
Merge "generalized highlighting of service cinder-volume"
Merge "do not exit after first invalid file"