[C++][Doc] Removed random. Changed uniformySample into randomConfiguration + Updated doc of joint-configuration algorithms. + reindentation

[C++] Changed exp/log functions to work also with segment of segment of vector or block of block of matrix

[C++][Python] Added a new macro for algorithms that work only with joint models instead of joint models and joint datas. Modified python binding and API accordingly

[C++][Python] Added algorithm working with joint configurations ( integrate, differentiate, interpolate, random, uniformlySample, distance), their python bindings and unittest

[C++][unittest] Fixed dynamics unittest. Initialize jacobians variables to avoid undefined behaviours

Lambda is a reserved keyword

Expose local_frame bool in RobotWrapper's jacobian proxy

Tests with unittests & coveralls

Add forward dynamics with contacts algorithm 

[Python] Some propositions about Format & Tests

https://www.python.org/dev/peps/pep-0008/

A few hints:
    + About Spaces:
        - always after a comma
        - never after [, (, {
        - never before ], ), }
        - always around -, +, *, **, %, ==, >=, <=
        - always around = for an assignation
        - never around = for a default value of an argument
        - never at the end of a line
    + One statement by line:
        - nothing after : unless inside []
        - no ;
    + No useless (), like in a simple if or assert
    + Indentation uses four spaces
    + Blanklines:
        - 2 before class or function declaration
        - 1 before class method declaration
        - never more than 2
    + Line length:
        - We said 79. This is far from beeign respected. Maybe 119 is more reasonable
    + Align:
        - at the begining of a line continuation
        - not multiple spaces before = to align multiple assignements

Of course, in our case, it would be tricky to follow some other rules, like:
    N802 function name should be lowercase
    N803 argument name should be lowercase
    N806 variable in function should be lowercase

Other issues may be addressed:
    F401 '<something>' imported but unused
    F403 'from <some_lib> import *' used; unable to detect undefined names

To check all of this:
    flake8 --ignore=N802,N803,N806 --max-line-length=119 <root_folder>

Other things changed:
    - import order (thanks isort)
    - useless elif changed to if
    - useless else removed
    - usage of ValueError, when an argument does not fit the expected type / size
    - issubclass(x.__class__, X) / x.__class__ == X → isinstance(x, X)
    - isinstance accepts a list or a tuple of classes (eg: isinstance(x, (int, float)))
    - print "" → print

Recreate resource retriever behaviour by specifying the ROS_PACKAGE_PATH as environment variable.

[C++][Geom Parser] put default value to empty vector of string for user hint directories. If user's hints and ROS_PACKAGE_PATH empty, then throw error. The function that parse ROS_PACKAGE_PATH doesn't throw errors anymore

[C++][Geom parser] Removed boolean root_joint_added while parsing. Geom parser modified consequently to look for parent of link in pinocchio model  now instead of urdf::tree parent joint.

[C++][Pyhton][Geom parser] ROS_PACKAGE_PATHS directories are now added to the ones specified by user

[Python] Update methods and RobotWrapper to use buildGeom instead of buildModelAndGeom and to use a list of package dirs instead of one meshRootDir.If no package_dirs is given by the user, then it will call the C++ procedure that automatically parse the ROS_PACKAGE_PATH

[Python] Added method to convert a python List of string to a C++ vector of string. Warning: the type checking must be made by user before using this function

[C++][Python][Parser Geom] Parse automatically the ROS_PACKAGE_PATH environment variable if not clue is given by the user to where to search for meshes. Change the meshRootDir argument to a vector of strings (package directories). Updated Python consequently

Improve doc of Model+Data and add python bindings in Travis