doc: clarify meaning of license abbreviation

[Bruno Haible]

Before changing anything in gnulib-tool and in the module descriptions
regarding licenses, I commit this patch, to clarify the currently understood
terms. This is so that lawyers like Karl Berry cannot claim afterwards that
I had done something "illegal".


2007-07-12  Bruno Haible  <address@hidden>

        * doc/gnulib-intro.texi (Copyright): Clarify the license abbreviations
        in the modules files.

*** doc/gnulib-intro.texi       16 Jan 2007 01:14:28 -0000      1.7
--- doc/gnulib-intro.texi       13 Jul 2007 00:46:56 -0000
***************
*** 212,218 ****
  Most modules are under the GPL.  Some, mostly modules which can
  reasonably be used in libraries, are under LGPL.  The source files
  always say "GPL", but the real license specification is in the module
! description file.
  
  More precisely, the license specification in the module description
  file applies to the files in @file{lib/} and @file{build-aux/}.  Different
--- 212,220 ----
  Most modules are under the GPL.  Some, mostly modules which can
  reasonably be used in libraries, are under LGPL.  The source files
  always say "GPL", but the real license specification is in the module
! description file.  If the module description file says "GPL", it currently
! means "GPLv2+" (GPLv2 or newer, at the licensee's choice); if it says "LGPL",
! it currently means "LGPLv2+" (LGPLv2 or newer, at the licensee's choice).
  
  More precisely, the license specification in the module description
  file applies to the files in @file{lib/} and @file{build-aux/}.  Different