build: configure: Use command line options to disable optional libraries

build: configure: Use command line options to disable optional libraries

Make the configure script accept command line options similar to the
autotools generated configure. Implement --disable-geoip and
--disable-zlib and use the to replace the respective DISABLE_* variables
introduced in 0349b93a6689a ("build: configure: Allow to disable support
for libgeoip and zlib").

Also update INSTALL and the travis CI configuration accordingly.

Based on previous work by Vadim Kochan.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>