nws 1.3.1
---------
1. Allow nwsListWss and nwsListVars to return result in data frame or string.
2. Split sleigh.R to several files
   - move sleighPending class to sleighPending.R
   - move internal functions to sleigh.internal.R
   - move workerLoop to workerLoop.R
   - move sshcmd, rshcmd, and lsfcmd to cmdLaunchOptions.R
3. Add launch.R which includes different ways to launch remote workers
   - web launch
   - cmd launch, which launches workers from worker script
4. Add DEBUG flag to eachElem and eachWorker
5. Add verbose mode to sleigh
6. Allow user to specify chunkSize of each task in eachElem invocation
7. Switched from make.socket to socketConnection to allow binary data
to be sent to the NWS server.
8  Changed serialization of objects from ascii to binary.
9. Added new example programs.
10. Add local launch mechanism, and made it the default launch method.
11. Fixed a problem where loading a saved R workspace fails if a sleigh
object was in the workspace.

nws 1.3.2
---------
1. Added support for service launch mechanism.
2. Properly quoted the commands to start the workers in addWorker function.
3. Added logDir option to sleigh constructor.
4. Changed the default working directory of workers to be the same as the
master.
5. Changed the rules for the "cmd launch functions" to return vectors rather
than strings.
6. Greatly improved the support for Windows in sleigh, including the
addition of Windows services for the executing the server, babelfish,
and sleigh workers.

nws 1.3.3
---------
1. Added nwsServer and netWorkSpace convenience functions.
2. Added sleighPro convenience function.
3. Fix rshcmd function to conform to Windows rsh cmd, and 
   add '-n' option to redirect standard input to /dev/null. 

nws 1.3.4
---------
1. Modified nwsStore to support the R 2.4 version of serialize.
2. Added prototype arguments to various setClass calls to prevent R from
instantiating default nwsServer objects which caused warning message during
build/installation.

nws 1.3.5
---------
1. Added some underlying support needed for fault tolerant versions of
   the eachElem and eachWorker sleigh methods.

nws 1.3.6
---------
1. Modified the RNWSSleighWorker scripts to use the value of the sleigh
   scriptDir option to help them find the nws package on the worker machines.
2. Modified workerLoop.R to print out more information in less space in
   the "worker info" variable.  Included the location of the log file
   and the version of R.
3. Fixed use of the export command in RNWSSleighWorker.sh that made it
   incompatible with some shells other than bash and zsh.

nws 1.4.0
---------
1. Added support for iterated operations.
2. Modified workerLoop.R to log errors to the sleigh workspace, in
   addition to the log file.

nws 1.5.0
---------
1. Fixed a bug in RNWSSleighWorker.py that causes a sleigh to fail.
   This is particularly a problem on Windows, where RNWSSleighWorker.py
   is the default worker script.
2. Created a workspace when constructing a sleigh that is reserved for
   the user.  The worker functions can access it via the SleighUserNws
   variable.
3. Added nwsStoreFile, nwsFindFile, nwsFileTryFile, nwsFetchFile, and
   nwsFetchTryFile methods to the netWorkSpace class.
4. Added error checking for optional arguments passed to sleigh,
   netWorkSpace, nwsOpenWs, and nwsUseWs.  That can help detect spelling
   errors that might otherwise go undetected.
5. Added the "closure" option to eachWorker and eachElem.  If it is set
   to FALSE, the enclosing environment will be removed, which may
   prevent transferring a huge amount of data in the serialized function
   of every task object.
6. Added warnings to eachWorker and eachElem if the worker function
   looks like a closure, but the "closure" option hasn't been explicitly
   specified.
7. Added status method to sleigh class.
8. Included the lsfSleigh launch function in the standard version of nws.
9. Removed sleighPro class, since all its functionality is in the
   standard sleigh class.
10. Included a new parallel kmeans sleigh example.
11. Added defaultSleighOptions environment that can be used to change
   the default options when constructing sleigh objects.
