fix all "pointer targets in assignment differ in signedness" warnings
fix all "pointer targets in assignment differ in signedness" warnings

sqlite3_column_text() returns a const unsigned char* to be extra careful
when supporting all platforms, since char is not guaranteed to be unsigned
but we only care about sane platforms where char is unsigned, so just cast
to const char*

guardianproject/libsqlfs,guardianproject/libsqlfs,eighthave/libsqlfs,eighthave/libsqlfs,spthaolt/libsqlfs,guardianproject/libsqlfs,eighthave/libsqlfs,eighthave/libsqlfs,guardianproject/libsqlfs,spthaolt/libsqlfs,spthaolt/libsqlfs,spthaolt/libsqlfs,guardianproject/libsqlfs,spthaolt/libsqlfs,eighthave/libsqlfs