Add sortpom to the project

[gbq6]

I'd like to add and apply sortpom to the project, if you have no objection @blacelle .

[blacelle]

What do you mean?

Sortpom is already enforced through Spotless (https://github.com/solven-eu/cleanthat/blob/master/parent/pom.xml):

	<pom>
		<includes>
			<include>pom.xml</include>
		</includes>
		<!-- https://github.com/diffplug/spotless/tree/main/plugin-maven#sortpom -->
		<sortPom>
			<!-- We like empty elements, while plugin default configuration would expand them -->
			<expandEmptyElements>false</expandEmptyElements>

			<!-- https://github.com/Ekryd/sortpom/issues/75 -->
			<spaceBeforeCloseEmptyElement>true</spaceBeforeCloseEmptyElement>

			<!-- https://github.com/Ekryd/sortpom/wiki/Parameters#for-both-the-sort-and-verify-goal -->
			<!-- -1 means '\t' -->
			<nrOfIndentSpace>-1</nrOfIndentSpace>
		</sortPom>
	</pom>

[gbq6]

Ah, sorry, the inconsistency in the empty lines tricked me. In that case, would you approve a pom cleanup? (Unifying empty lines, removing many years old commented out code (not including actual comments), moving versions and scopes to dependency-management where applicable?)

[blacelle]

would you approve a pom cleanup?

Certainly.