#206 Override include directories

[BDB]

When a custom include directory is added to the
project, it is added to the makefile AFTER the Dev-Cpp
default include directories. They should go in front so
that user include files will override anything in the
default directories.

For instance, say I want to include vector.h, an
include file I wrote containing a CVector class. If I
try to include vector.h then g++ thinks I want to
include the STL vector header, not MY vector header.