Added comment about required feeing of return value.
Little history precessing improvement.

The history files and items list must be made unique so we generated a list
and removed old items that where equal to a new to insert item. This caused
some deletions in the GList that are not necessary. Now the file lines are
processed from the last to the first. That means, every new item (older item
in file) that is already is in the list can be discarded, because the latest
is already in the GList.
Include config.h in every c file and include it first.
Another history processing improvement.

Don't translate file lines into history or bookmarks structs, if we have
enough unique items in the processed list (history max items). So it's not
necessary to convert the lines and to remove them in a second step from the
list.
Don't put 'about:*' uri into history.
Removed vimb.1.txt to process manpage direct for install target.
Removed nearly empty makefile for manual page.
Removed -Wstrict-prototypes option that won't work with gtk.
Simplified Makefile by merging CPPFLAGS into CFLAGS.
Put similar target in Makefile together.

Added LDFLAG -s to strip symbol table to build smaller binary.
Fixed wrong free function in history processing.

Also moved freeing to the caller.
Moved config for default window size to config.def.h.

Increased the default windo size to 800x600.
Use PROJECT variable instead of hard wired "vimb".
Updated README file.
Moved configuration for the shell command to config.def.h.
Added queue commands :push and :pop.
Added new hinting mode to put links into queue.

Also added new default keybinding to open oldest queued item in current window
'ctrl-p'.
Fixed wrong bookmark lookup.

If the completion for bookmarks was started with given tags, there where also
items displayed that have no tags set. This patch fixes the regression so that
only those bookmarks are shown thats tags match the request, all other
bookmarks can only be seen when the completion is started without tags like
':open !<tab>'.
Added queue feature to README.
Allow to switch off queue feature via config.h.