Version, history and license.
 
 - 2017-01-01 Hartmut now obsolete, the CmdExecuterhas a queue too. Because CmdStore is obsolete. Content is removed.
- 2016-12-31 Hartmut new: #addCmd(org.vishia.cmd.JZcmdScript.Subroutine, List, File)
- 2016-09-18 Hartmut new: #addCmd(CmdBlock, CmdGetterArguments)new concept supports onlyJZtxtcmdExecuterThe#addCmd(String, File, boolean)and#addCmd(String[], File, boolean)is newly designed for simple operation system
   command execution without JZcmd concept. The#addCmd(CmdBlock, File[], File)which prepares file parts is designated as deprecated.
   Instead the JZcmdExecuter with more capability should be used.
- 2016-09-18 Hartmut chg: ctor with null as log, don't use log and JZcmd for simple applications. 
 
- 2015-07-18 Hartmut chg: Now associated to an Appendable instead a PrintStream for error alive and error messages.
   A System.out is an Appendable too, for this kind the application is unchanged. Other output channels may support
   an Appendable rather than an PrintStream because it is more simple and substantial. 
 
- 2013-09-08 Hartmut new: #jzcmdExecuternow included. TODO: it should use the#executerinstead create a new one per call.
- 2013-02-09 Hartmut chg: #abortCmd()now clears the queue too. The clearing of the command queue is a good idea, because while a program execution hangs, some unnecessary requests
 may be initiated.
- 2013-02-03 Hartmut chg: better execution exception, uses log in #execCmds(Appendable)
- 2013-02-03 Hartmut chg: #execCmds(Appendable)with only one parameter, the second one was unused.
- 2011-12-03 Hartmut chg: The #pendingCmds-queue containsPendingCmdinsteadCmdStore.CmdBlocknow. It is one level near on the really execution. A queued
   command may not stored in a CmdBlock.
- 2011-11-17 Hartmut new #close()to stop threads.
- 2011-07-00 created
 
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