removed all .msg source, because we don't need it, and it causes problem with rosbuild (#3232)

core/roslib/msg/Clock.msg

@@ -1,4 +0,0 @@
-# roslib/Clock is used for publishing simulated time in ROS. 
-# This message simply communicates the current time.
-# For more information, see http://www.ros.org/wiki/Clock
-time clock

core/roslib/msg/Header.msg

@@ -1,15 +0,0 @@
-# Standard metadata for higher-level stamped data types.
-# This is generally used to communicate timestamped data 
-# in a particular coordinate frame.
-# 
-# sequence ID: consecutively increasing ID 
-uint32 seq
-#Two-integer timestamp that is expressed as:
-# * stamp.secs: seconds (stamp_secs) since epoch
-# * stamp.nsecs: nanoseconds since stamp_secs
-# time-handling sugar is provided by the client library
-time stamp
-#Frame this data is associated with
-# 0: no frame
-# 1: global frame
-string frame_id

core/roslib/msg/Log.msg

@@ -1,19 +0,0 @@
-##
-## Severity level constants
-##
-byte DEBUG=1 #debug level
-byte INFO=2  #general level
-byte WARN=4  #warning level
-byte ERROR=8 #error level
-byte FATAL=16 #fatal/critical level
-##
-## Fields
-##
-Header header
-byte level
-string name # name of the node
-string msg # message 
-string file # file the message came from
-string function # function the message came from
-uint32 line # line the message came from
-string[] topics # topic names that the node publishes