Stop tracking generated files

* files, generated as side-effect of running ``configure'' script,
* files, generated by ``configure'' script (Makefile, config.h),
* ``telegram'' binary.

All these files are setup-dependent and differ between targets.

.gitignore

 *.o
+Makefile
+autom4te.cache
+config.h
+config.log
+config.status
+telegram