Address LP: #565101
* debian/eucalyptus.conf: set default JVM_MEM option
* debian/eucalyptus-common.eucalyptus.upstart: use $JVM_MEM
  from eucalyptus.conf, or default to 512m
* tools/eucalyptus.conf.5: document the JVM_MEM option

Cherry-pick upstream commit r1223..1227:
* node/handlers.c, node/handlers_kvm.c: handle situation where NC's
  do not detach pthreads, LP: #567371
* node/handlers_kvm.c: fix console bug (was only showing first 64K),
  LP: #566793
* clc/modules/storage-common/src/main/java/edu/ucsb/eucalyptus/storage/StorageManager.java,
  clc/modules/storage-common/src/main/java/edu/ucsb/eucalyptus/storage/fs/FileSystemStorageManager.java,
  clc/modules/walrus/src/main/java/edu/ucsb/eucalyptus/cloud/ws/WalrusImageManager.java,
  clc/modules/walrus/src/main/java/edu/ucsb/eucalyptus/cloud/ws/WalrusManager.java,
  clc/modules/wsstack/src/main/java/com/eucalyptus/ws/handlers/ServiceSinkHandler.java:
  - fix Walrus OOM errors (java heap), LP: #565101