chg: remove manual reload logic
chgserver now validates and reloads configs automatically. Manually reloading
is no longer necessary. Besides, we are deprecating pid files since the server
will periodically check its ownership of the socket file and exit if it does
not own the socket file any longer, which works more reliable than a pid file.
This patch removes the SIGHUP reload logic from both chg server and client.
Test issue2761
$ hg init
$ touch to-be-deleted
$ hg add
adding to-be-deleted
$ hg ci -m first
$ echo a > to-be-deleted
$ hg ci -m second
$ rm to-be-deleted
$ hg diff -r 0
Same issue, different code path
$ hg up -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ touch does-not-exist-in-1
$ hg add
adding does-not-exist-in-1
$ hg ci -m third
$ rm does-not-exist-in-1
$ hg diff -r 1