add support yaml file

[yueyijingque]

Use snakeyaml to read the yaml configuration file, flatten it, and set it to the properties of MavenProject

[slawekjaranowski]

Thanks for efforts.

I was introduce a service for reading/writing properties in #113 .

Please simply implements: PropertiesManager
https://github.com/mojohaus/properties-maven-plugin/tree/master/src/main/java/org/codehaus/mojo/properties/managers

I close it, as code will be more different - we need a new PR.