Updated Kalzium documentation

[Yuri Chornoivan]

Hi!

An updated Kalzium docbook can be found in git master. The docbook was
prepared for Kalzium 2.4 so there is no titration calculator documentation
in it (planned on the time when this docbook will be moved to KDE 4.7
branch).

PDF version can be found here:
http://ompldr.org/vOXk0bQ/kalzium.pdf

I'd really appreciate if someone reviews it and gives the hints on what
should added/improved.

Thanks in advance for your advices.

Best regards,
Yuri