Fix some issues reported by lintian

Changes-By: lintian-brush
Fixes: lintian: cute-field
See-also: https://lintian.debian.org/tags/cute-field.html

Changes-By: lintian-brush
Fixes: lintian: debian-rules-uses-as-needed-linker-flag
See-also: https://lintian.debian.org/tags/debian-rules-uses-as-needed-linker-flag.html

Changes-By: lintian-brush
Fixes: lintian: package-uses-old-debhelper-compat-version
See-also: https://lintian.debian.org/tags/package-uses-old-debhelper-compat-version.html

Fix some issues reported by lintian

Fixes: lintian: upstream-metadata-file-is-missing
See-also: https://lintian.debian.org/tags/upstream-metadata-file-is-missing.html


Fixes: lintian: upstream-metadata-missing-bug-tracking
See-also: https://lintian.debian.org/tags/upstream-metadata-missing-bug-tracking.html


Fixes: lintian: upstream-metadata-missing-repository
See-also: https://lintian.debian.org/tags/upstream-metadata-missing-repository.html

Fixes: lintian: uses-debhelper-compat-file
See-also: https://lintian.debian.org/tags/uses-debhelper-compat-file.html

Fixes: lintian: package-uses-old-debhelper-compat-version
See-also: https://lintian.debian.org/tags/package-uses-old-debhelper-compat-version.html

Fixes: lintian: insecure-copyright-format-uri
See-also: https://lintian.debian.org/tags/insecure-copyright-format-uri.html

Conflicts:
	README

Fixed bug about maintainer scripts (preinst, postinst, prerm, postrm) of the package guidedog does not start with #!

Added comments in source code about button behavior.