Fixing some things

[graysonkoy]

Currently, reports output like this:

<packages >
	<package ...>
		<class ...>
			<methods >
			</lines>
		</class>
		<class ...>
			<methods >
			</lines>
		</class>
	</package>
</packages>

They should look like this:

<packages>
	<package ...>
		<classes>
			<class ...>
				<methods>
				</lines>
			</class>
			<class ...>
				<methods>
				</lines>
			</class>
		</classes>
	</package>
</packages>

Differences:

• There should be a <classes> tag surrounding the <class> tags
• There shouldn't be a trailing space following tag names when there aren't any attributes

This PR fixes these things.

[bacebu4]

Thanks for the contribution!

Sorry for late reply. I'll review this change within a day and release it if everything will work correctly