Workaround AX_PREFIX_CONFIG_H issue

It seems that AX_PREFIX_CONFIG_H does not catch the case when
there are space between # and define.  One such situation arises
when calling AC_C_BIGENDIAN with no arguments.  We now call it with
an argument and create our own define with a different name.
Change contact email to p4est@librelist.com
Update AUTHORS
Remove sc_c99_functions.h
Add issue on make lint and friends
sc_blas.m4: fix false negative in blas config

SC_BLAS_LINK does not set sc_blas_ok=yes on success, we have to set that first
and then let it set sc_blas_ok=no if it fails.
Fix false negative in lapack config