Bug#560414: lintian: Don't warn about length of short description of text templates

[Frans Pop <elendil@planet.nl>]

Package: lintian
Version: 2.2.18
Severity: wishlist
X-Debbugs-CC: debian-boot@lists.debian.org

Concerns check: too-long-short-description-in-templates

As can be seen on [1] there are a lot of warnings of this type, especially 
for udebs. For udebs all cases are templates of type "text" that contain 
text fragments that get dynamically included in other templates at 
runtime. Because of that specific usage, the length of the short 
description is not relevant.

To avoid these false positives, please add an exception for this warning:
- if the template type is "text" AND
- the package is a udeb

Reasons to request the exception are:
- udebs cannot contain lintian exceptions for binary packages (because we
  don't want them installed in the D-I environment)
- we *do* want the warning for other template types than "text"

[1]http://lintian.debian.org/tags/too-long-short-description-in-templates.html