new cmd dipatcher 

hi pct

I did some 2 changes

change 1
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I removed plac module and wrote a Command Dispatcher which provide easy way to add new sub commands and have better help format:

example of command:

usage: vimpyre [-h]
               
               {search,install,browse,uninstall_all,update,remove,update_all,init,list_installed,remove_all,uninstall}
               ...

optional arguments:
  -h, --help            show this help message and exit

subcommands:
  {search,install,browse,uninstall_all,update,remove,update_all,init,list_installed,remove_all,uninstall}
                        additional help
    browse              browse script's homepage in your web browser
    init                intialize enviroment
    install             install scripts
    list_installed      list installed scripts
    remove              remove scripts
    remove_all          remove all scripts
    search              search script
    uninstall           remove scripts
    uninstall_all       remove all scripts
    update              update scripts
    update_all          update all scripts

example of sub command

usage: vimpyre install [-h] [scripts [scripts ...]]

positional arguments:
  scripts     script1 script2 ...

optional arguments:
  -h, --help  show this help message and exit

change 2
=======

1. ingnore temp files created by ez_setup tools