[myhdl-list] [PATCH 0 of 2 V2] Add support for negative indexes

[Angel E. <ang...@gm...>]

This is a second, cleaner and more complete version of this patch series.

The first patch has not changed compared to the previous version of this patch series. On the other hand, the second patch should work much better, and should
support both negative numbers as indexes and explicit negative operations through
the negative unary operation.