Log Message:
libyaml: update to 0.2.2.

Changes
=======

* https://github.com/yaml/libyaml/pull/95 -- build: do not install config.h
* https://github.com/yaml/libyaml/pull/97 -- appveyor.yml: fix Release build
* https://github.com/yaml/libyaml/pull/103 -- Remove unused code in \ 
yaml_document_delete
* https://github.com/yaml/libyaml/pull/104 -- Allow colons in plain scalars \ 
inside flow collections
* https://github.com/yaml/libyaml/pull/109 -- Fix comparison in tests/run-emitter.c
* https://github.com/yaml/libyaml/pull/117 -- Fix typo error
* https://github.com/yaml/libyaml/pull/119 -- The closing single quote needs to \ 
be indented...
* https://github.com/yaml/libyaml/pull/121 -- fix token name typos in comments
* https://github.com/yaml/libyaml/pull/122 -- Revert removing of open_ended \ 
after top level plain scalar
* https://github.com/yaml/libyaml/pull/125 -- Cherry-picks from PR 27
* https://github.com/yaml/libyaml/pull/135 -- Windows/C89 compatibility
* https://github.com/yaml/libyaml/pull/136 -- allow override of Windows static \ 
lib name