Change FILE to TAG in help text displayed by config.status

[John Calcote]

When you enter './config.status --help' at the command line, you get:

   $ ./config.status --help
   `config.status' instantiates files from templates according to the
   current configuration.

   Usage: ./config.status [OPTION]... [FILE]...
   ...

The 'Usage' line above should read:

   Usage: ./config.status [OPTION]... [TAG]...

in order to be consistent with the documentation in the manual. The use 
of file in this location can also be somewhat confusing relative to 
other uses of the term FILE in this same help text. For example, in the 
--file and --header options:

   ...
         --file=FILE[:TEMPLATE]
                      instantiate the configuration file FILE
         --header=FILE[:TEMPLATE]
                      instantiate the configuration header FILE
   ...

A user might confuse the use of FILE in the Usage line with the use of 
FILE in these options.

Regards,
John