Stop classifying digits as lower case letters in wikilinks

Fixes #842

core/modules/parsers/wikiparser/rules/wikilink.js

@@ -25,7 +25,7 @@ exports.types = {inline: true};
 
 var textPrimitives = {
 	upperLetter: "[A-Z\u00c0-\u00d6\u00d8-\u00de\u0150\u0170]",
-	lowerLetter: "[a-z0-9\u00df-\u00f6\u00f8-\u00ff\u0151\u0171]",
+	lowerLetter: "[a-z\u00df-\u00f6\u00f8-\u00ff\u0151\u0171]",
 	anyLetter:   "[A-Za-z0-9\u00c0-\u00d6\u00d8-\u00de\u00df-\u00f6\u00f8-\u00ff\u0150\u0170\u0151\u0171]",
 	blockPrefixLetters:	"[A-Za-z0-9-_\u00c0-\u00d6\u00d8-\u00de\u00df-\u00f6\u00f8-\u00ff\u0150\u0170\u0151\u0171]"
 };