Fix typos in kwargdict snippet [skip ci]

docs/markdown/snippets/kwargdict.md

@@ -2,7 +2,7 @@
 
 You can now specify keyword arguments for any function and method call
 with the `kwargs` keyword argument. This is perhaps best described
-with an example.
+with an example:
 
 ```meson
 options = {'include_directories': include_directories('inc')}
@@ -20,9 +20,9 @@ executable(...
   include_directories: include_directories('inc'))
 ```
 
-That is, Mesn will expand the dictionary given to `kwargs` as if the
+That is, Meson will expand the dictionary given to `kwargs` as if the
 entries in it had been given as keyword arguments directly.
 
 Note that any individual argument can be specified either directly or
-with the `kwarg`` dict but not both. If a key is specified twice, it
+with the `kwarg` dict but not both. If a key is specified twice, it
 is a hard error.