RFR: 8030681 : (s) add "serve" command and --quiet and --verbose options to hgforest

[Mike Duigou]

Hello all;

This is a patch which adds support for the "serve" command to hgforest as well as providing --quiet and --verbose options.

The serve command is particularly useful for sharing repos with virtual machines used for building/testing. Using "serve" is generally faster and has fewer problems than using shared filesystems (let me tell you! I if I have to delete one more .hg/store/lock file... Well, you don't want to know what would happen!)

https://bugs.openjdk.java.net/browse/JDK-8030681

http://cr.openjdk.java.net/~mduigou/JDK-8030681/2/webrev/

This issue was originally created for another purpose, "--subrepo", that is being deferred to a future issue. Changes to hgforest to support the "trees" extension are likely coming and I wanted to get these changes out of the way before other hgforest changes complicate things.

Cheers,

Mike