HADOOP-2916. Refactor src structure, but leave package structure alone. (Raghu Angadi via mukund)

Files:
added: /hadoop/core/trunk/src/hdfs/org/apache/hadoop (try)
modified: /hadoop/core/trunk/build.xml (try)
added: /hadoop/core/trunk/src/mapred (try)
copied: from /hadoop/core/trunk/src/java/org/apache/hadoop (r664208) to /hadoop/core/trunk/src/core/org/apache/hadoop (try)
added: /hadoop/core/trunk/src/hdfs/org (try)
added: /hadoop/core/trunk/src/benchmarks (try)
added: /hadoop/core/trunk/src/core/org (try)
added: /hadoop/core/trunk/src/mapred/org/apache (try)
copied: from /hadoop/core/trunk/src/test/gridmix (r664208) to /hadoop/core/trunk/src/benchmarks/gridmix (try)
deleted: /hadoop/core/trunk/src/java
deleted: /hadoop/core/trunk/src/test/gridmix
deleted: /hadoop/core/trunk/src/core/org/apache/hadoop/mapred
copied: from /hadoop/core/trunk/src/java/org/apache/hadoop/dfs (r664208) to /hadoop/core/trunk/src/hdfs/org/apache/hadoop/dfs (try)
added: /hadoop/core/trunk/src/hdfs (try)
deleted: /hadoop/core/trunk/src/core/org/apache/hadoop/dfs
added: /hadoop/core/trunk/src/core (try)
added: /hadoop/core/trunk/src/mapred/org/apache/hadoop (try)
added: /hadoop/core/trunk/src/hdfs/org/apache (try)
added: /hadoop/core/trunk/src/mapred/org (try)
modified: /hadoop/core/trunk/CHANGES.txt (try)
added: /hadoop/core/trunk/src/core/org/apache (try)
copied: from /hadoop/core/trunk/src/java/overview.html (r664208) to /hadoop/core/trunk/src/core/overview.html (try)
copied: from /hadoop/core/trunk/src/java/org/apache/hadoop/mapred (r664208) to /hadoop/core/trunk/src/mapred/org/apache/hadoop/mapred (try)