Workaround Netty bug by not use CompositeByteBuf

Due a bug in Netty [1] using a CompositeByteBuf can lead to data-corruption when partial writes happen on a socket. To workaround this bug we replaced the CompositeByteBuf usage (which was caused by Unpooled.wrappedBuffer(...)).

Beside work around the Netty bug this also reduce the object creation and so should stay in place even after Netty will be upgraded to 4.0.22.Final.

This commit also reverted the partial workaround that was in place before.

[1] https://github.com/netty/netty/issues/2761

patch by normanm; reviewed by tjake for CASSANDRA-7695
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Remove duplicates from StorageService.getJoiningNodes
patch by jbellis; reviewed by ayeschenko for CASSANDRA-7478
merge from 1.2
merge from 1.2
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Fix race in background compaction check

patch by yukim; reviewed by krummas for CASSANDRA-7745
Merge branch 'cassandra-1.2' into cassandra-2.0

Conflicts:
	CHANGES.txt
Merge branch 'cassandra-2.0' into cassandra-2.1.0
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Don't depend on cassandra config for nodetool ring

Backport of CASSANDRA-7508 to cassandra-2.0 by Tyler Hobbs
Merge branch 'cassandra-2.0' into cassandra-2.1.0

Conflicts:
	CHANGES.txt
	src/java/org/apache/cassandra/tools/NodeCmd.java
Merge branch 'cassandra-2.1.0' into cassandra-2.1
Add CqlOutputFormat
patch by Paul Pak; reviewed by Piotr Kołaczkowski for CASSANDRA-6927
export MALLOC_ARENA_MAX corrrectly

Patch by brandonwilliams, reviewed by jbellis for CASSANDRA-6126
export MALLOC_ARENA_MAX corrrectly

Patch by brandonwilliams, reviewed by jbellis for CASSANDRA-6126
Merge branch 'cassandra-2.0' into cassandra-2.1
Add new CMS GC flags on Windows launch scripts for JVM > 7u60

Patch by Josh McKenzie, reviewed by jbellis for CASSANDRA-7714
backport CASSANDRA-6927 to 2.0
fix changes