Fixes #5, Add travis support

Don't clean when building, otherwise the sophia db will be removed after
cloning.

Append flags instead of overwriting if empty, this way travis build
can supply custom CFLAGS.

Link shared library with CC instead of LD.
Merge branch 'master' of github.com:sphia/libsphia into add-travis-support

Conflicts:
	.gitignore
	Makefile
Merge pull request #19 from sphia/add-travis-support

Add travis support