Get rid of OS specific file path separators

as suggested by @linkrope in #17 (comment).
Not tested yet on Windows as locally not available, currently. Runs wel on Linux.

src/gamma/main.d

@@ -230,29 +230,22 @@ void build(string[] fileNames, string outputDirectory)
 {
     import core.stdc.stdlib : exit;
     import std.format : format;
-    import std.path : stripExtension;
+    import std.path : buildPath, stripExtension;
     import std.process : spawnProcess, wait;
     import std.string : join;
 
-    auto args = "dmd" ~ fileNames ~ "-g" ~ "include/runtime.d"
-        ~ "src/io.d" ~ "src/log.d" ~ "src/epsilon/soag/listacks.d";
+    auto args = "dmd" ~ fileNames ~ "-g" 
+        ~ buildPath("include", "runtime.d")
+        ~ buildPath("src", "io.d") 
+        ~ buildPath("src", "log.d") 
+        ~ buildPath("src", "epsilon", "soag", "listacks.d"); 
 
     if (!outputDirectory.empty)
     {
         args ~= format!"-od=%s"(outputDirectory);
         args ~= format!"-of=%s"(fileNames.front.stripExtension.executableName);
     }
 
-    version(Windows) 
-    {
-        import std.string : translate;
-        for(int i; i < args.length; i++) 
-        {
-            dchar[dchar] translation = ['/': '\\'];
-            args[i] = translate(args[i], translation);
-        }
-    }
-
     info!"%s"(args.join(' '));
 
     auto pid = spawnProcess(args);