Each command has a description (displayed on the button on the main page),
and an actual command to execute. This command string can contain shell
operators like |, > and ; for executing multiple commands and pipelines.
The string can also contain parameters like $foo, which are replaced
by user inputs when the command is run. 
These parameters can be entered into the table at the bottom of the page.
For each parameter you must enter :
- Name
- A unique code for this parameter. If the name is foo, then
    $foo will be replaced by the parameter value when the command
    is executed.
 
- Description
- The description next to this parameter on the main page.
 
- Type
- This option controls how the parameter is input. Available options are :
	
	- Text
 A totally free-text input.
- User
 A username from your system.
- UID
 The UID of a user from your system.
- Group
 A group name from your system.
- GID
 The GID of a group from your system.
- File
 The full path to a file.
- Directory
 The full path to a directory.
- Option
 A Yes/No input that will set the parameter to whatever is in
	    the field next to the type input only if Yes is chosen.
- Password
 A totally free-text input, but with the password replaced by *'s.
- Menu
 A drop-down menu of options, taken from the filename entered into
	    the text field to it. Or, instead of a filename you can enter a
	    command with an | at the end, whose output will be used to determine
	    the available options.
- Upload
 An input box for selecting a file on the client side, which will be
	    uploaded to the server when the command is run. This will be be
	    placed in a temporary file, and the path to that file will be the
	    value of this parameter when the command is run.
- Textbox
 A multi-line free text field. When the command is run, any newline
	    characters in the entered text will be converted into spaces.
 
    In most cases, the default value for the parameter will be whatever you
    enter in the text box next to the parameter type menu.
 
- Quote parameter?
- If Yes, the parameter will be quoted with " before substitution, allowing
    the user to enter values containing whitespaces.