Save also page title in history file (#46).
Save page title also in bookmark file (#46).
Avoid glist to transfer completion data to the completion.c.

The completion asked the required components to spit out the list of
completion items to make a GtkListStore model and fill it with the data and to
free the list. Now we let the component like history, bookmark or setting fill
in the completion items self, which avoids unneeded list preparation and
memory allocation.
Show page title in history and bookmark completion (#46).
Reapplied sorting of completion entries.
Allow to enable/disable title in completions on compile time.
Added change bookmark file format to README.
Moved default config from config.h to own file.

This make the inclusion if the config.h file easier.
Replaced the confg.h by config.def.h file.
Added announcement for change history file format.
Moved feature config from config.mk to config.def.h.
Added another pre-compiler flag to enable announcement.

This makes it easier to remove the announcement via sed script or other
automated scripts.
Disabled the gtk progressbar feature per default like before.
Merge branch 'history-titles'