Bug#733272: uscan syntax for opts=pasv

[Osamu Aoki]

Hi,

In general, user environment dependent configuration should not be a
part of the watch file.  So putting opts=pasv for the released package
is not a good idea.  --pasv or USCAN_PASV should be used.

As for opts= syntax, something should be persistent and most should not.

In multitar branch, I have rewritten manpage to address concerns raised
on this bug as its side effects.

|  The following non-comment lines (watch lines) specify the
|  e selection of the candidate upstream tarball URLs and are in
|  following 3 formats:
|  ·   opts=" ... " http://URL matching-pattern [version
|  ·   http://URL matching-pattern [version [script]]
|  ·   opts=" ... "

(Yes, it is OK to have opts= only line in version=4.  But valid only for
persistent option.)
  
|  ...
|  
|  Unless otherwise noted as persistent, most options are valid only
|  within the watch line.
|  
|  ...

persistent ones are (at this moment)
 compression
 user-agent

Osamu