Change generated operator function names to EQUALS/ASSIGN
Change generated operator function names to EQUALS/ASSIGN

Attempting to continue my series of five-minute changes this week, I
remembered in looking at the generated code today that ever since Vass
hired on I've been meaning to look into whether we could code generate
'=' as "ASSIGN" and '==' as "EQUALS" rather than the current scheme of
using "EQUALS" and "EQUALS_EQUALS" for these operators.  (Rationale
being that every time I see "EQUALS" in the generated code I mentally
think it means "==" rather than assignment).

Turns out that this was more like a 15 minute change and turned out
not as clean/pretty as I would like, arguably because the original
code that does these renamings is not particularly elegant (lots of
little strings getting allocated and cobbled together on a
character-by-character basis, followed by starting over on the string
from the first character again).  Added a bunch of comments to my new
code soothe my guilt somewhat and received absolution from Vass and
Greg over IM (the only ones among you whose opinions I value... :).




git-svn-id: 88467cb1fb04b8a755be7e1ee1026be4190196ef@18135 3a8e244f-b0f2-452b-bcba-4c88e055c3ca

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