Fix documentation nits

Just minor spelling and grammar fixes.

Change-Id: I2dc98e4b68ac2df35fe1647cd4af3402cd55d77d
diff --git a/doc/source/developer/docs.rst b/doc/source/developer/docs.rst
index 6a7256e..0a8bfe5 100644
--- a/doc/source/developer/docs.rst
+++ b/doc/source/developer/docs.rst
@@ -65,7 +65,7 @@
 entire hierarchy of the attribute, but emphasises the last portion
 (i.e., the field being documented).
 
-To use the hierarchical features, simply nest with indendtation in the
+To use the hierarchical features, simply nest with indentation in the
 normal RST manner.
 
 It supports the ``required`` and ``default`` options and will annotate