Fix issue for pkg-config export of the lib

Improve support of CMake >= 3.0.0

Update package.xml to fix unstable build warnings

Follow-up fix for PYTHON_EXT_SUFFIX

Fix MSVC compile errors

...\eigenpy\src\eigenpy.cpp : fatal error C1128:
number of sections exceeded object file format limit: compile with /bigobj

quaternion: fix exposure of toRotationMatrix

Update cmake

Expose all real-valued specialised Eigen types

travis: add bionic + make parallel

cmake: sync submodule

Add warnings when implicitly using numpy.matrix.

Minor smoothing + sync submodule cmake