attempted split of Learning Manual

[Graham Percival]

I tried splitting the learning manual, but I had problems with the 
translations.  If you'd rather junk my three commits and do it again 
from scratch, go ahead.

Problems:
- why the Mao does each language have their own macros.tely?!  I was 
expecting that I could simply copy the file from the main docs to the 
translations.

- how do I check for broken links?  With the english docs, I do "make 
web" and get a screen-full of "texinfo can't resolve this @ref{}", which 
I faithfully resolve.  When I tried the doing "make web" in the 
translation directories, I didn't get any warnings.  I didn't even get 
those messages when I did "make web" from the top dir.

- Graham