order 1 to 5
fix crb.hpp in branch
update issue #174 : _M -> M_
@vincentchabannes update issue #155: start work on adding a new key to isOnBoundary in order to
select element with respect to the sub-entity they share the boundary with
(point, edge, face)
fix issue #174
fix issue #174
fix issue #173
added traits for location iterators
update issue #155 implement boundary element iterators such that we can pick either all of the
them or depending the on the sub-entity of the element touching the boundary
(point edge, face)
update issue #175: do not use gmsh refine in 3D (and in fact neither in 2D)