Merge changes I67890f52,I33c72799

* changes:
  usage.dox: fix encoder/decoder subpage list indent
  usage.dox: fix doxygen warnings in 1.8.x

usage.dox

@@ -12,13 +12,13 @@
     - \ref usage_init
     - \ref usage_errors
 
-    Fore more information on decoder and encoder specific usage, see the
+    For more information on decoder and encoder specific usage, see the
     following pages:
     \if decoder
-    - \subpage usage_decode
+    \li \subpage usage_decode
     \endif
-    \if decoder
-    - \subpage usage_encode
+    \if encoder
+    \li \subpage usage_encode
     \endif
 
     \section usage_types Important Data Types
@@ -81,12 +81,12 @@
 
     The available initialization methods are:
     \if encoder
-     - #vpx_codec_enc_init (calls vpx_codec_enc_init_ver())
-     - #vpx_codec_enc_init_multi (calls vpx_codec_enc_init_multi_ver())
-     .
+    \li #vpx_codec_enc_init (calls vpx_codec_enc_init_ver())
+    \li #vpx_codec_enc_init_multi (calls vpx_codec_enc_init_multi_ver())
+    \endif
+    \if decoder
+    \li #vpx_codec_dec_init (calls vpx_codec_dec_init_ver())
     \endif
-    \if decoder - #vpx_codec_dec_init (calls vpx_codec_dec_init_ver()) \endif
-
 
 
     \section usage_errors Error Handling

usage_cx.dox

@@ -1,4 +1,4 @@
-/*! \page usage_encode Encode
+/*! \page usage_encode Encoding
 
     The vpx_codec_encode() function is at the core of the encode loop. It
     processes raw images passed by the application, producing packets of