Added new option --inject=KEY[,KEY...]

If you have a typed metadata key which contains an amount, you can use
--inject=KEY to inject a posting with that amount wherever a match
occurs.  There are two main forms of usage:

  2010-06-18 Sample
      ; Key:: $100
      Expenses:Food                $100.00
      Assets:Checking

The command would be:

  ledger reg --inject=Key

In the above, transactional form, a posting under the account "Key" will
be injected before the first posting reported for this transaction.
It's amount will be $100.  This only happens once for the whole
transaction.

It is also possible to associate the key with a posting:

  2010-06-18 Sample
      Expenses:Food                $100.00
      ; Key:: $100
      Assets:Checking

Now the injected posting is generated whenever that particular post is
reported.

1 files changed, 4 insertions, 0 deletions

diff --git a/src/chain.cc b/src/chain.cc
index 64550663..8010ba74 100644
--- a/src/chain.cc
+++ b/src/chain.cc
@@ -258,6 +258,10 @@ post_handler_ptr chain_post_handlers(post_handler_ptr base_handler,
   if (report.HANDLED(related))
     handler.reset(new related_posts(handler, report.HANDLED(related_all)));
 
+  if (report.HANDLED(inject_))
+    handler.reset(new inject_posts(handler, report.HANDLED(inject_).str(),
+                                   report.session.journal->master));
+
   return handler;
 }