bump up version to 0.97.0-alpha.3
Update #279: move subelements() function into its own header
update #279 : use new subelements.hpp header
update #279: split reinit_fms

 - reinit_fms.cpp is renamed reinit_fms_impl.hpp
 - reinit_fms_inst_{2d,3d}.cpp instantiate the Fast Marching Method in 2D and 3D respectively
ignore
added license/copyright in quickstart examples
`feel options()` is now set automatically using `_desc_lib` (#273)
update #279: more explicit options in Exporter
 - `exporter.geometry` is a string : change_coords_only, change or static 
 - `exporter.file-type` is a string : ascii, binary

the former allows to save a lot of disk space of used in static mode (only one
mesh saved) otherwise by default change_coords_only will tell the ensight
reader to load only the point coordinates for faster mesh load

Conflicts:
	feel/options.cpp