[m-rev.] for review: replace item_blocks with parse trees during pre-HLDS passes

[Zoltan Somogyi]

For review by Julien, since he kindly volunteered.
Thank you in advance. Note that some of the XXXs
in the log message are questions for you. I would
also appreciate it if, besides reviewing the diff, you
also tried it out on the programs you are working on.

Zoltan.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Log.pt
Type: application/octet-stream
Size: 28193 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20200310/6fb587f5/attachment-0001.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: DIFF.pt.gz
Type: application/x-gzip
Size: 268823 bytes
Desc: not available
URL: <http://lists.mercurylang.org/archives/reviews/attachments/20200310/6fb587f5/attachment-0001.bin>