Add empty inline constrain*() functions to be usable even when constraints are disabled at compile-time - it should be as easy as possible for users to future-proof their currently-non-adaptive code.
Add empty inline constrain*() functions to be usable even when
constraints are disabled at compile-time - it should be as easy as
possible for users to future-proof their currently-non-adaptive code.



git-svn-id: ffc1bc5b3feaf8644044862cc38c386ade156493@3340 434f946d-2f3d-0410-ba4c-cb9f52fb0dbf

certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh,certik/libmesh