Now correctly tests not using the Rust standard library.

Added the ability to correctly create a TestLogger when not
using the standard library. This was done by creating a constant
TestLogger and a set_logger function that returned a constant pointer
to the constant logger.

examples/logger.rs

@@ -7,6 +7,11 @@ use scribe::{Levels, Logger, Record};
 
 
 
+#[cfg(not(feature="use_std"))]
+const core_logger: TestLogger = TestLogger {};
+
+
+
 pub struct TestLogger
 {
 }
@@ -45,6 +50,7 @@ impl TestLogger
       }
    }
 
+   #[cfg(feature="use_std")]
    fn set_logger() -> Box<Logger>
    {
       let logger: TestLogger;
@@ -56,6 +62,12 @@ impl TestLogger
 
       Box::new(logger)
    }
+
+   #[cfg(not(feature="use_std"))]
+   fn set_logger() -> *const Logger
+   {
+      &core_logger
+   }
 }
 
 impl Logger for TestLogger