revlog: use an explicit config option to enable mmap usage for index
We replace the `experimental.mmapindexthreshold` with two options:
The `storage.revlog.mmap.index` is a boolean option to enable or disable the
feature. The `storage.revlog.mmap.index:size-threshold` is a bytes option that
control when we will be using mmap instead of plain reading.
import sys
for line in sys.stdin:
if line.lower() in ("message-id: \n", "in-reply-to: \n"):
line = line[:-2]
print(line, end="")