Convert example to exemplar

* Rename example files to exemplar

See exercism/docs#23

* [Docs] Correct .meta/example references to .meta/exemplar

* [Docs] Use exemplar instead of example

* [Docs] Update example name in file listings

* [Julia] Convert to exemplar.jl

* [elm] Rename .meta/Cook.elm to .meta/Examplar.elm

* [elm] Rename .meta/Examplar.elm .meta/Exemplar.elm

Co-authored-by: Matthieu Pizenberg <matthieu.pizenberg@gmail.com>

Author: 2 people

exercises/concept/basics/.meta/example.go exercises/concept/basics/.meta/exemplar.go

@@ -40,7 +40,7 @@ languages
                 ├── .meta
                 |   |── config.json
                 |   |── design.md
-                |   └── example.go
+                |   └── exemplar.go
                 ├── <NAME>.go
                 └── <NAME>_test.go
 </pre>
@@ -51,7 +51,7 @@ The code files are track-specific and should be designed to help the student lea
 
 - `<NAME>.go`. the stub implementation file, which is the starting point for students to work on the exercise.
 - `<NAME>_test.go`: the test suite.
-- `.meta/example.go`: an example implementation that passes all the tests.
+- `.meta/exemplar.go`: an exemplar implementation that passes all the tests.
 
 ## Step 2: Add documentation files