XD 166 & XD 143

Added registry.type property to drive the channel registry properties
  - Added commandLine options to support registry.type
  - "redis" is set as default registry type
Added config/redis.properties & config/rabbit.properties as properties files
  - Refer properties as file:${xd.home}/config/{registry.type}.properties

Fix redis config support
  Add profile based application context based on the pipeProtocol (redis, rabbit, local)
  Updated application context xml with redis profile
  Removed embedded options from the xd admin & container scripts
  Added pipeProtocol as the command line option to the container & admin
  Set spring.profiles.active system property based on the middleware option chosen
refactoring of the original PR (#39)

* renamed pipeProtocol to transport and removed enum

* replace profile-driven transport configs with property-driven

* added transports subdirectory and included redis-* config files

* refactored common code for AdminMain and ContainerMain
Merge pull request #42 from markfisher/XD-166

XD-166 refactored the original PR #39