Projects moved under correct parent.
Moved code-generator/maven-yang -> yang/.
Moved code-generator/maven-yang-plugin -> yang/.
Moved code-generator/maven-yang-plugin-it -> yang/.
Moved code-generator/yang-model-parser-api -> yang/.
Moved code-generator/yang-model-parser-impl -> yang/.
Configured site plugin for project. Fixed some javadocs.
Fixed bug in ParserUtils causing NullPointerException.
Fixed bug in resolving uses statement.
Improved tests.
Change-Id: Ia7567544fbe006f0cf87055c6633c04b5ce2c50e
Signed-off-by: Martin Vitez <mvitez@cisco.com>