Fix build on Linux

On the current Ubuntu/GCC order of linker flags seem to matter.
Also added the `export LD_LIBRARY_PATH=.` to relevant targets, to make sure it is documented and everything runs from the makefile.

Signed-off-by: Stefan Marr <git@stefan-marr.de>
Added .travis.yml

Signed-off-by: Stefan Marr <git@stefan-marr.de>