#6 Fix --prologue/--epilogue

[Stephen Clouse]

This patch makes the --prologue and --epilogue options
actually work. Currently you just get a fatal if you
try to use them.

This patch also enables the use of multiple
--prologue/--epilogue options (which will be joined
together if the same section is specified multiple
times), and also allows an embedded \n escape sequence,
so multi-line RPM fragments can be appended (like an
%ifarch/%else block).

[Stephen Clouse]