tests: use scenarios attributes for timeout capability

Change-Id: I78931eca9478289e5c643ce37364e059d8009728
Update links + python version supported

Use the right git link and the tested python versions.

Change-Id: Id1b244671e3aec982bdf713a38ff8fae22ac8dfe
Sync requirements to global requirements

For better tooz adoption, we'll need the requirements to be sync'ed
to global requirements. sysv_ipc is only on linux platforms and NOT
on windows platforms, and as it is a optional plugin, let's specify
that in test-requirements

Change-Id: I4c9e1098dbcd480a2efdf3c73acb99431fe0b242
Depends-On: If934a117039b4101190aba98dfe33ae491027956
Depends-On: I9660a0af74e8b43942f99a6f889213b457cd85db
Merge "Sync requirements to global requirements"
Merge "tests: use scenarios attributes for timeout capability"
Merge "Update links + python version supported"
A few more documentation tweaks

- Capitalize tooz where appropriate.
- Adjust contents to be an actual header.
- Add a footnote that states tooz can be generally useful
  for anyone (and not just openstack projects); this was taken
  from taskflows similar footnote.

Change-Id: I9b4e0304483e2c7155f4d5107fd2967ed2c8d1a4