build-matrix: Speed up with unary notation

4.6s -> 3.9s.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Fix target name check

This makes it error out when
    make MXE_TARGETS=i686-w64-mingw32.stati
etc.

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Add message when i686-pc-mingw32 is used

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
flex, libpng: Use $(SOURCEFORGE_MIRROR)

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
flex: Update

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
move geotiff to cmake. link error on shared libs blocking gdal
GEOS: enable shared library mingw64
GDAL: enable shared library for mingw64 with as much as drivers
OpenCV: enable shared libs. tested on mingw64
Proj4: enable shared libs. tested on mingw64
OpenCV: fix include path
libgeotiff: check correct proj4 headers from cmake configure
ITK: patch stat and execvp for x86_64
ADD
Added new package names to index.html
REVIEW: qwt_qt4 downgrade to 5.2