Update docs:

- Some comments in hip_hcc.cpp
 - document hipHostRegister* flags.
 - expand docs on hipHostRegister/Unregister. Use "register" rather than
   "pin" to describe action these take.
 - change required CUDA version to 6 (require unified memory)
 - remake doxygen.

hipamd/docs/RuntimeAPI/html/search/variables_8.js

@@ -1,4 +1,4 @@
 var searchData=
 [
-  ['sharedmemperblock',['sharedMemPerBlock',['../structhipDeviceProp__t.html#a3b9138678a0795c2677eddcfb1c67156',1,'hipDeviceProp_t']]]
+  ['regsperblock',['regsPerBlock',['../structhipDeviceProp__t.html#a73c1c21648a901799ff6bef83c11135b',1,'hipDeviceProp_t']]]
 ];