Minor fixes for lintian checks

[fabfurnari]

Fix as many issues as possible:

E: rectification changes: bad-distribution-in-changes-file theodoric
W: rectification source: changelog-should-mention-nmu
W: rectification source: source-nmu-has-incorrect-version-number 1.2-0archeos2
E: rectification: description-starts-with-package-name
W: rectification: binary-without-manpage usr/bin/rect
W: rectification: desktop-entry-invalid-category Photogrammetry usr/share/applications/rectification.desktop
E: rectification: description-starts-with-package-name
W: rectification: binary-without-manpage usr/bin/rect
W: rectification: desktop-entry-invalid-category Photogrammetry usr/share/applications/rectification.desktop