[v3] tr1 headers and file naming conventions

[Benjamin Kosnik]

(thanks for the new, spell-checked subject!)

>To get the Doxygen magic happening, either (1) the indoxygenation scripts have 
>to be modified to pick up the header names explicitly, or 

We should do this anyway. Care to give it a go? There are considerable
holes in the current coverage of doxygen. Perhaps Phil can help us out
with this...

>(2) the tr1 
>extensionless headers should be made to work just like the existing standard 
>headers, ie. through the Makefile mechanism.  Consistency with existing 
>practise is good.

Let's try not to do this.

-benjamin