Add Catalan (ca) locale (thanks to @Dimas-sc)

(#59)

chrome.manifest

@@ -1,6 +1,7 @@
 content privatetab ./
 
 locale privatetab en-US locale/en-US/
+locale privatetab ca    locale/ca/
 locale privatetab de    locale/de/
 locale privatetab el    locale/el/
 locale privatetab es    locale/es/

install.rdf

@@ -1,4 +1,4 @@
-<?xml version="1.0"?>
+<?xml version="1.0"?>
 
 <RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
 	 xmlns:em="http://www.mozilla.org/2004/em-rdf#">
@@ -31,6 +31,16 @@
 			</Description>
 		</em:targetApplication>
 
+		<em:localized>
+			<Description>
+				<em:locale>ca</em:locale>
+				<em:name>Private Tab</em:name>
+				<em:description>Adds private tabs</em:description>
+				<em:creator>Infocatcher</em:creator>
+				<em:translator>Dimas-sc</em:translator>
+			</Description>
+		</em:localized>
+
 		<em:localized>
 			<Description>
 				<em:locale>de</em:locale>

locale/ca/pt.properties

@@ -0,0 +1,25 @@
+openInNewPrivateTab=Obre l'enllaç en una pestanya privada nova
+openInNewPrivateTabAccesskey=v
+
+openPlacesInNewPrivateTab=Obre en una nova pestanya privada
+openPlacesInNewPrivateTabAccesskey=v
+
+privateTab=Pestanya privada
+privateTabTip=(pestanya privada)
+privateTabAccesskey=v
+
+openNewPrivateTab=Pestanya privada nova
+openNewPrivateTabTip=Obre una pestanya privada nova
+openNewPrivateTabAccesskey=v
+# For SeaMonkey
+openNewPrivateTabShort=Pestanya privada
+openNewPrivateTabShortAccesskey=v
+
+# For SeaMonkey, you can just copy Firefox translation
+privateBrowsingTitleModifier=\ (Navegació privada)
+
+# Confirmation dialog in case of extension disabling or uninstalling
+dialogTitle=Pestanya privada
+dialogQuestion=Hi ha %S pestanya(es) privada(es). Què vols fer?
+dialogClose=&Tancar-la(es)
+dialogRestore=Fer-la(es) &no-privada(es)