conn_rec -> master

[Stefan Eissing <st...@greenbytes.de>]

As discussed before, I want to propose backporting changes that require
the "master" member in conn_rec. Those were introduced in trunk with 1565657:

  http://svn.apache.org/viewvc?view=revision&revision=r1565657

but I would favor ("like") the backporting of just the addition of

+    /** The "real" master connection. NULL if I am the master. */
+    conn_rec *master;

only as the whole array of slave connections is not used by anyone 
yet and I am not certain that the final design will look like it.

Backport proposal of a partial change by referring tot he change
and providing own patch?

//Stefan