added coedit project to test mixin err mesg

lazproj/test/coeditproj/mixin_errfile_data.coedit

@@ -0,0 +1,20 @@
+object CurrentProject: TCEProject
+  OptionsCollection = <  
+    item
+      name = 'release'
+      outputOptions.boundsCheck = offAlways
+      pathsOptions.Imports.Strings = (
+        '..\src\'
+      )
+      preBuildProcess.options = []
+      preBuildProcess.showWindow = swoNone
+      postBuildProcess.options = []
+      postBuildProcess.showWindow = swoNone
+      runOptions.options = [poUsePipes, poStderrToOutPut]
+      runOptions.showWindow = swoNone
+    end>
+  Sources.Strings = (
+    '..\src\mixin_errfile_main.d'
+  )
+  ConfigurationIndex = 0
+end

lazproj/test/src/mixin_errfile_data.txt

@@ -0,0 +1 @@
+writeln("hello runnable module);

lazproj/test/src/mixin_errfile_main.d

@@ -0,0 +1,10 @@
+module runnable;
+
+import std.stdio;
+
+void main(string args[])
+{
+    // purpose: test if error message in mixed content could be clicked
+    // => no, the filename from where the data come is not passed
+    mixin(import("mixin_errfile_data.txt"));
+}