Get rid of some compiler warning messages

Prevents the compiler from complaining about conversion from string to
char*.

closes #791
Stop compiler complaining about HAVE_SNPRINTF

This undefines HAVE_SNPRINTF in the fife wrapper to prevent the compiler
from complaining about it.  I don't *think* there were be any problems with
this.
Ignore swig warnings

From now on we ignore a few swig warnings that we cannot (or will not) do
anything about.  This includes the warning 404 (already wrapped) and
warning 473 (returning a pointer or reference in a director).

fixes #792
Merge branch 'master' of https://github.com/fifengine/fifengine