Docs: add CHANGELOG.md
Docs: add CHANGELOG.md

Ref #15
Closes gh-104

szarouski/jscs-jsdoc,MunGell/jscs-jsdoc,shaoshing/jscs-jsdoc,lvivier/jscs-jsdoc,dtracers/jscs-jsdoc,jdlrobson/jscs-jsdoc,jscs-dev/jscs-jsdoc