[LMH]Documentation

[Emmanuel Rialland]

I just made the commit to have change bars when using the environment 
/TIcomment.

James made some footnote comments. What about using a separate environment 
for them too? That way we keep the possibility to scrap them off completely 
to revert to the original TI version. 

For the moment I see those TIcomments and footnotes as 2 separate levels of 
explanations: footnotes for immediate semantic / context clarification; 
TIcomments for lengthy ramblings about the universe in general and the e3 in 
particular.

Emmanuel