[epochs] Boost conditional dependency map

From: Joaquin M López Muñoz (joaquinlopezmunoz_at_[hidden])
Date: 2020-06-05 17:23:32

As part of the epoch proposal, I've written a small toolchain to 
generate a so-called
Boost conditional dependency map:

https://github.com/joaquintides/boostcdmap/

Such a map gives, for each Boost module and each epoch Boost03, ... , 
Boost20, the
dependencies of the module under the given epoch (which may vary across 
epochs).
The actual map for Boost 1.73 is provided at:

https://github.com/joaquintides/boostcdmap/blob/master/boostcdmap.1.73.0.json

The conditional dependency map is a key asset for the automation of 
epoch assignment;
I'll elaborate on this point in the upcoming days.

As always, comments welcome. Best regards,

Joaquín M López Muñoz