merge upstream master

[bill-auger]

merge with current upstream master from http://git.savannah.gnu.org/r/smalltalk.git

it appears that most of the branches on this fork are stale - these are the current upstream branches

 * [new branch]      master     -> upstream/master
 * [new branch]      stable-2.1 -> upstream/stable-2.1
 * [new branch]      stable-2.2 -> upstream/stable-2.2
 * [new branch]      stable-2.3 -> upstream/stable-2.3
 * [new branch]      stable-3.0 -> upstream/stable-3.0
 * [new branch]      stable-3.2 -> upstream/stable-3.2

there are also the following tags which would need to be pushed manually

 * [new tag]         3.2.5      -> 3.2.5
 * [new tag]         3.2.91     -> 3.2.91