Adds a list of contributors

Thanks folks !
Merge branch 'master' into writing

* master:
  Adds a list of contributors
Remove useless "fake task to gather facts".

Facts are gathered already if the hosts are named. There is no need
for a fake task, it only clutters the output with useless messages.
Grammatical improvements.

See pull #5.
Merge pull request #44 from htgoebel/master

Remove useless "fake task" and grammatical improvements (branch master)
Merge branch 'master' into writing

* master:
  Grammatical improvements.
  Remove useless "fake task to gather facts".

Conflicts:
	step-11/README.md
Introduces facts more smoothly

Facts were presented with 'More facts' but weren't mentionned before.
Fixes #52