[Development] Proposal: New list of Qt 5 reference / Tier 1 platforms

[Charley Bay]

> Friedemann said he'd like to have msvc 2010 64 bit as reference platform,
> maybe replacing msvc 2010 32 bit.

Really?  I would assume that 32-bit is still a significantly-large
audience that we could *add* 64-bit, but that we likely would need to
keep 32-bit (for a while).

Have developers really cut-over to 64-bit *deployment*?  (We only
deploy 32-bit to enable a single set of binary-installers for many
target platforms, including embedded, even though yes, some of those
target platforms happen to be 64-bit.)

If msvc 2010 32-bit is dropped as "reference/tier-1", then we would
probably need to update our deployment to have two sets of installers
(32-bit because of embedded needs, but also 64-bit because that would
be the new "reference/tier-1").

This is only an observation (not a criticism) -- we'd like to take our
embedded to 64-bit eventually, but I'm unsure of when the
"generic-user-base" will no longer have a plethora of 32-bit-Windows
user operating systems.

So, question:  How many developers target 64-bit Windows exclusively
(not 32-bit-Windows)?  (Has that day come?)

--charley