FIX: Dead lines at the bottom on the list.

Fix bug introduced in 60f61bd, dead lines stayed on the screen while
the list shrunk.
FIX: ChangeLog readability

More like a ChangeLog, less like a git log.
Command used: git log --format="%ai %aN <%aE>%n%n%x09* %s%n" > ChangeLog
FIX: Update display every second even in the absence of new lines
FIX: Diplay consistency in curses mode
ADD: check-syntax in Makefile for Flymake
UPDATE: Display improvment

 * ADD: Header line
 * Unifying line format
Splitting code, first step to provide a lib_logtop.
Renaming logtop -> main (see next commit)
Renaming frequency -> logtop, more consistent
Provide a logtop_delete function, renames for consistency
Adding a logtop_get function
Simplier to use a struct for swig
Adding python module via swig