Accept numbers in # and ## preprocessor tokens (#2449)

Author: wixoaGit

Content.Tests/DMProject/Tests/Preprocessor/number_in_arg.dm

@@ -0,0 +1,4 @@
+#define MACRO(ARG_1, ARG_2) "[#ARG_1] [##ARG_2]"
+
+/proc/RunTest()
+	ASSERT(MACRO(1, 2) == "1 2")

DMCompiler/Compiler/DMPreprocessor/DMPreprocessorLexer.cs

@@ -442,7 +442,7 @@ public Token NextToken(bool ignoreWhitespace = false) {
                 }
 
                 TokenTextBuilder.Clear();
-                while (char.IsAsciiLetter(GetCurrent()) || GetCurrent() == '_') {
+                while (char.IsAsciiLetterOrDigit(GetCurrent()) || GetCurrent() == '_') {
                     TokenTextBuilder.Append(GetCurrent());
                     Advance();
                 }