Added an exception on invalid lua file, made some more clean up to fit C++11
Added missing filename to new exception
Fixed licensing
Changed compile time constants to constexpr
Cleaned up a little more
Fixed terrible bug that 4dventure will throw an exception if you do have a valid game map instead of the opposite.

Update recommended!

--HG--
branch : stable
Added tag 1.1.3 for changeset bf0213b5e4be

--HG--
branch : stable
merged stable