add repetition code notebook (#718)

* add repetition code notebook

* tidy up text

* index repetition code notebook (and fix a typo in another)

* fix issues with indexing of Hello_Qiskit

* add repetition code to readme

Author: quantumjim

community/creative/random_terrain_generation.ipynb

@@ -776,7 +776,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "keywords = {'Topics': ['Creative','Games','Procedural generation','Images','Entanglement'], 'Commands': ['`ry`','`initialize','`noise_model`','`basic_device_noise_model`']}"
+    "keywords = {'Topics': ['Creative','Games','Procedural generation','Images','Entanglement'], 'Commands': ['`ry`','`initialize`','`noise_model`','`basic_device_noise_model`']}"
    ]
   }
  ],

community/games/Hello_Qiskit.ipynb

@@ -34565,21 +34565,14 @@
     "All this goes to show that quantum variables don't always follow the logic we are used to. They follow different rules, the rules of quantum mechanics, which will allow us to find ways of performing computation in very different ways than we are used to."
    ]
   },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
-    "### Keywords\n",
-    "Topics: *Games*, *Bell inequality*. <br /> \n",
-    "Commands: `x`, `z`, `h`, `cx`."
-   ]
-  },
   {
    "cell_type": "code",
    "execution_count": null,
    "metadata": {},
    "outputs": [],
-   "source": []
+   "source": [
+    "keywords = {'Topics': ['Games', 'Bell inequality', 'Entanglement'], 'Commands': ['`x`', '`z`', '`h`', '`cx`']}"
+   ]
   }
  ],
  "metadata": {

community/ignis/readme.md

@@ -14,6 +14,8 @@ In this folder we have a collection of great tutorials from our fantastic Qiskit
 
 * [Randomized Benchmarking](RB_overview.ipynb): Introduction to randomized benchmarking (RB), which is a scalable technique for measuring the average gate error. 
 
+* [Repetition Code](repetition_code.ipynb): A guide to compiling repetition code circuits to run on real devices.
+
 ## Contributing
 
 Quantum characterization is such an interesting topic and we have by no means covered everything! We welcome additional notebooks in the relevant folder.