Add CFEngine syntax checker.
CFEngine syntax checker: remove notes.  Add syntax warning and error tests.
Update changelog
Update Elixir in testing VM

Update test cases accordingly
Fix and improve list of supported languages
Merge branch 'master' into tzz-master

* master: (64 commits)
  Fix and improve list of supported languages
  Update Elixir in testing VM
  Update changelog
  [Fix #280] Make relative imports work for Pylint
  Use underscore to separate temp prefix and name
  Fix required checkers for Ruby tests
  Fix test names
  Merge puppet-lint test cases
  Remove unused resources
  Sort autoloads
  Add autoload for adoc-mode
  Fix test case name
  Update changelog and credits
  Add AsciiDoc to README
  Require old cl for mocker.el
  Use a common naming pattern for all tests
  Do not require libraries up front
  Add test for syntax errors from ruby-lint
  Update Ruby tests
  Fix name of libxslt header package
  ...

Conflicts:
	doc/flycheck.texi
	flycheck.el
	test/builtin-checkers-test.el
Fix test names
Install Cfengine on the test VM
Install Cfengine mode
Fix cfengine tests
Update README, changelog and credits

Thanks for your contribution, @tzz
[Fix #271] Merge branch 'tzz-master'

* tzz-master:
  Update README, changelog and credits
  Fix cfengine tests
  Install Cfengine mode
  Install Cfengine on the test VM
  Fix test names
  CFEngine syntax checker: remove notes.  Add syntax warning and error tests.
  Add CFEngine syntax checker.
Install the latest Erlang on the test VM