First draft of FieldGenerator and function Battlefield.create
Merge branch 'master' of https://github.com/VLanvin/GL_MPRI_2014
Typo (forest instead of water)

Be warned though! `Tile.create_from_file` won't be used that way
in an uncertain future!
Fix compilation issue
Merge branch 'master' of https://github.com/VLanvin/GL_MPRI_2014
Merging engine (1/2)