The internal pre-processor ignored lines that did not parse a calendar
entries, but did not support multi-line comments in the way the external
cpp did.
The calendar files distributed with the base system (now in a port) do
use comments, though.
Implement comment processing for single-line (//) and multi-line comments
(/* */) with same semantics as in a standard C pre-processor.
All tests pass with this version, but there are no tests that specifically
verify comment processing.
Reported by: jhs@berklix.com (Julian H. Stacey)
MFC after: 3 days
0f352f4e25