Fix doc syntax and formatting

Author: jmikola

docs/reference/method/MongoDBCollection-createIndex.txt

@@ -82,7 +82,7 @@ exists.
 
    <?php
 
-   $collection = (new MongoDB\Client)->selectCollection('test, 'restaurants');
+   $collection = (new MongoDB\Client)->selectCollection('test', 'restaurants');
 
    $indexName = $collection->createIndex(
       ['borough' => 1],

docs/reference/method/MongoDBCollection-deleteMany.txt

@@ -78,5 +78,5 @@ See Also
 - :phpmethod:`MongoDB\\Collection::deleteOne()`
 - :phpmethod:`MongoDB\\Collection::bulkWrite()`
 - :doc:`/tutorial/crud`
-- :manual:`delete </reference/command/delete` command reference in the MongoDB
+- :manual:`delete </reference/command/delete>` command reference in the MongoDB
   manual

docs/reference/method/MongoDBCollection-deleteOne.txt

@@ -80,5 +80,5 @@ See Also
 - :phpmethod:`MongoDB\\Collection::deleteMany()`
 - :phpmethod:`MongoDB\\Collection::bulkWrite()`
 - :doc:`/tutorial/crud`
-- :manual:`delete </reference/command/delete` command reference  in the MongoDB
+- :manual:`delete </reference/command/delete>` command reference  in the MongoDB
   manual

docs/tutorial/example-data.txt

@@ -39,7 +39,7 @@ The output would then resemble::
 You may also import the datasets using :manual:`mongoimport
 </reference/program/mongoimport>`, which is included with MongoDB:
 
-.. code-block:: none
+.. code-block:: sh
 
-   $ mongoimport --db test --collection zips --file zips.json --drop
-   $ mongoimport --db test --collection restaurants --file primer-dataset.json --drop
+   mongoimport --db test --collection zips --file zips.json --drop
+   mongoimport --db test --collection restaurants --file primer-dataset.json --drop