Merge remote-tracking branch 'origin/purge'

* origin/purge:
  implement public-inbox-purge tool
  v2writable: read epoch on purge
  v2writable: cleanup processes when done
  v2writable: purge ignores non-existent git epoch directories
  v2writable: ->purge returns undef on no-op
  import: purge: reap fast-export process
  hoist out resolve_repo_dir from -index

diff --cc MANIFEST
Simple merge

diff --cc script/public-inbox-index
index 2ae92757cac6607ec9c6658df3c221c5900dcddb,32121f6d9a5650edc566803e41107d339f8978e6..5adb6e741eff8f2578a780bd40738cd7c42ee7a6
--- 1/script/public-inbox-index
--- 2/script/public-inbox-index
+++ b/script/public-inbox-index
@@@ -9,12 -9,13 +9,13 @@@
  use strict;
  use warnings;
  use Getopt::Long qw(:config gnu_getopt no_ignore_case auto_abbrev);
- use Cwd 'abs_path';
  my $usage = "public-inbox-index REPO_DIR";
  use PublicInbox::Config;
+ use PublicInbox::Admin qw(resolve_repo_dir);
+ 
  my $config = eval { PublicInbox::Config->new } || eval {
        warn "public-inbox unconfigured for serving, indexing anyways...\n";
 -      {}
 +      undef;
  };
  eval { require PublicInbox::SearchIdx };
  if ($@) {