patchrequest-pull: short sha handling, manual update

> request-pull prints incorrectly warn messages about not found commits 
> and man pages don't say
> anything about todays changed behaviour. People are confused and try 
> look for errors at wrong places.
> At least these should be fixed/modified.
>
> Warn massage says that commit can't be found ar remote, however there 
> it is in and is missing on local repository
> in 'many' cases. So I don't know if better solution is check, where 
> commit is truly missing or transform warning message.
> Something like:
>
>    warn: No match for commit <commit> found at <url> or local repository.
>    warn: Are you sure you have synchronized branch with remote 
> repository?
>
> ......
> man page could be changed like this:
>
> -------------------------------------------------------
> diff --git a/Documentation/git-request-pull.txt 
> b/Documentation/git-request-pull.txt
> index 283577b..6d34fc7 100644
> --- a/Documentation/git-request-pull.txt
> +++ b/Documentation/git-request-pull.txt
> @@ -73,6 +73,17 @@ then you can ask that to be pulled with
>         git request-pull v1.0 https://git.ko.xz/project master:for-linus
>
>
> +NOTES
> +-----
> +
> +Since git version 2.0.0 is behaviour of git request-pull little 
> different.
> +It is recommended use of third argument for each request-pull, otherwise
> +you can get error message like:
> +
> +   warn: No match for commit <commit> found at <url>
> +   warn: Are you sure you pushed 'HEAD' there?
> +
> +
>  GIT
>  ---
>  Part of the linkgit:git[1] suite
>
> -------------------------------------------------------
>
> Second patch provides right processing of third parameter when short 
> version of sha hash is used (e.g. 897a111). Now is
> supported only full hash, what is different behaviour against first 
> parameter or what can be found in other functions. Extra
> solves one of cases of wrong warn message.
>
> -------------------------------------------------------
> diff --git a/git-request-pull.sh b/git-request-pull.sh
> index d5500fd..2dc735e 100755
> --- a/git-request-pull.sh
> +++ b/git-request-pull.sh
> @@ -92,9 +92,11 @@ find_matching_ref='
>                 chomp;
>                 my ($sha1, $ref, $deref) = /^(\S+)\s+([^^]+)(\S*)$/;
>                 my ($pattern);
> +               my ($pattern2);
>                 next unless ($sha1 eq $headrev);
>
>                 $pattern="/$head\$";
> +               $pattern2="^$head";
>                 if ($ref eq $head) {
>                         $found = $ref;
>                 }
> @@ -104,6 +106,9 @@ find_matching_ref='
>                 if ($sha1 eq $head) {
>                         $found = $sha1;
>                 }
> +               elsif ($sha1 =~ /$pattern2/ and (length $head) gt 7) {
> +                       $found = $sha1
> +               }
>         }
>         if ($found) {
>                 print "$found\n";
> -------------------------------------------------------