Compute zmp from force sensors in the feet.

  Some initializations that used to be performed in this package were in fact
  application dependent. These initializations have been moved to the new
  package sot-application.
  - class solver has been removed,
  - features and tasks are not created anymore in AbstractHumanoidRobot class.

This commit remove files and references which are now in different packages.

The code can now compile without.

Specified -ldynamic.so whereas this package does not generate
libdynamic.so file. Instead this is :
${CMAKE_INSTALL_PREFIX}/lib/plugin/dynamic.so
which is generated.
Further modifications will be needed to support other platforms.

  This reverts commit 46085b6b.

	  * CMakeLists.txt,
	  * src/dynamic_graph/sot/dynamics/__init__.py,
	  * doc/CMakeLists.txt: new,
	  * doc/sphinx/conf.py.in: new,
	  * doc/sphinx/index.rst.in: new.

* Use PKG_CONFIG_USE_DEPENDENCY for jrl-dynamics and hrp2-dynamics
* Fix other minor dependency issues

Corrected leftover code from a test. Kept LIST2STRING macro in the file just in case, will be removed if all link bugs are resolved.

Added documentation stubs. Made hrp2Dynamics required (for some reason this was commented out) again.

Especially, the folders for hrp2 could not be found