[Libreoffice] How do I update my download?

Hi, sorry for a beginner's question, but I downloaded the libreoffice 
code base from git about a month ago, and I want to update it to be the 
same as the recently released version 3.3 without having to download it 
all again. Can anyone help out? I think, but am not sure, that the 
version I have is what in cvs is called the head - not sure about git 
terminology.

If it is too hard to convert to version 3.3, then how do I simply update 
the version I have from the current git repositories?

Info: I am an expert C++ programmer, but have never used git, nor have I 
any familiarity (yet) with the libo code base, so please be specific.

(BTW, this would be good to add to the help page on libreoffice.org.)

Cheers,
Ron.

--
Ron House
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