Fixing doc/tests

src/writers/graphics_640x480x16.rs

@@ -15,8 +15,11 @@ static PLANES: &'static [Plane] = &[Plane::Plane0, Plane::Plane1, Plane::Plane2,
 ///
 /// Basic usage:
 ///
-/// ```
+/// ```no_run
+/// use vga::Graphics640x480x16;
+///
 /// let graphics_mode = Graphics640x480x16::new();
+///
 /// graphics_mode.set_mode();
 /// graphics_mode.clear_screen();
 /// ```

src/writers/text_40x25.rs

@@ -20,8 +20,11 @@ static BLANK_CHARACTER: ScreenCharacter = ScreenCharacter {
 ///
 /// Basic usage:
 ///
-/// ```
+/// ```no_run
+/// use vga::Text40x25;
+///
 /// let text_mode = Text40x25::new();
+///
 /// text_mode.set_mode();
 /// text_mode.clear_screen();
 /// ```

src/writers/text_40x50.rs

@@ -20,8 +20,11 @@ static BLANK_CHARACTER: ScreenCharacter = ScreenCharacter {
 ///
 /// Basic usage:
 ///
-/// ```
+/// ```no_run
+/// use vga::Text40x50;
+///
 /// let text_mode = Text40x50::new();
+///
 /// text_mode.set_mode();
 /// text_mode.clear_screen();
 /// ```

src/writers/text_80x25.rs

@@ -20,8 +20,11 @@ static BLANK_CHARACTER: ScreenCharacter = ScreenCharacter {
 ///
 /// Basic usage:
 ///
-/// ```
+/// ```no_run
+/// use vga::Text80x25;
+///
 /// let text_mode = Text80x25::new();
+///
 /// text_mode.set_mode();
 /// text_mode.clear_screen();
 /// ```