Removed ugly sysout
Moved plugins, features and themes

They are now all under extension
Added also  the reflection dependency and the need xml-apis jar to avoid
conflicts in integration tests
Updated HTML IT (JSP impl)

New test for empty and null source when using DOM source
Moved JSP inside dom and ajax directories for a clearer organization and
updated existing IT accordingly
Draft of base utility classes for new export

Linked with dandelion/issues#80
Removed jsonp attribute from both TLDs
Upgraded Thymeleaf to 2.0.17
Optimized html tag generation

Fixed dandelion/issues#130
Improved logging during configuration loading
Updated CdnITs

Linked with dandelion/issues#130
Removed commons-lang dependency from core

* And updated all classes accordingly
* ReflectHelper renamed to ClassUtils

Linked with dandelion/issues#132
Removed commons-lang dependency

Cleaned POMs
Removed dead code
Linked with dandelion/issues#132
Create CONTRIBUTING.md