Plural forms needed for the print view

[Mario Blättermann]

The print view uses the plural always when telling about the count of items and pages. This reads some odd when only one item on one page ist to be printed.

Screenshot:
https://lh3.googleusercontent.com/Jl9RqnPdlgTxdtwsjwWs-h9mLrVbRF_mSLqnPhlFmvTF_qPKGfpbIxk8cfLRsotE1JY4IyClI9hmhRgDPpYmvhhuTuvG2ejzk3xIpWgDNNPv9avGR8ElHwHSCCf9xGAQU8eTmQagRER7euBVBdZ0Fntn-wv4qIuqVymVq0Ki0FprzjBVokPy29zIvYW-vku-5AIzmeviggEKnV3awnzPX4J0mIC1iIda6fDHQ8AeVd9tp60pPGksKNk-De0DMLrlRpX1_yMUjHWaC9UAKII_7U6UCmxUDQs8bcPrIPIDNij22CUnCHWk7pzoeVKBBeUFNn1ywi5_yr9pDRBGU1HjmoTO5yyFaU4gtksAi150Ab2bEOTYqhucrBAH0JBQSHNrPWoy5F8-Z6v8Vc3h7CrBZNcKwkbLg2oS_f0d1_A_e-QvbAD-KErDuLgucQ3wfrWPnCV-mV0eZmxENKFo3rGExTVX8I0zCia1xYIYRdX6lv2BK3wrn_t_Nksr2JmM33j4kWhwZwZ9uTOgdTP0rChXivj4hLaD9EktUAZXUvtGCHJtIFRF-Atr9XRfvTbXaymrAJVELFVjlIqy2Y3ECrKTarXwW49Sy-KjsqtgAx_60Kfztgx7pncUgrBor1pD8YdJa3Cv4_r6gGM2v_bgekszOct8kw=w330-h182-no

The corresponding source code is in glabels/PrintView.cpp:

	void PrintView::updateView()
	{
		copiesStartSpin->setRange( 1, mModel->frame()->nLabels() );

		copiesDescriptionLabel->setText( tr("(Will print a total of %1 items on %2 pages.)")
		                                 .arg(mRenderer.nItems()).arg(mRenderer.nPages()) );

		pageSpin->setRange( 1, mRenderer.nPages() );
		nPagesLabel->setText( QString::number( mRenderer.nPages() ) );
	}

Some plural forms definition is needed here.

[J Evins]

Low hanging fruit. Addressed in 6be243d.