[DOCS] update titles to reflect tutorial content (nnvm vs. relay) (#2597)

* update titles to reflect tutorial content (nnvm vs. relay)

* move things around

* fix typo

tutorials/autotvm/tune_relay_arm.py

 """
 Auto-tuning a convolutional network for ARM CPU
-====================================================
+===============================================
 **Author**: `Lianmin Zheng <https://github.com/merrymercy>`_, `Zhao Wu <https://github.com/FrozenGene>`_, `Eddie Yan <https://github.com/eqy>`_
 
 Auto-tuning for a specific ARM device is critical for getting the best
@@ -193,7 +193,7 @@ tuning_option = {
         builder=autotvm.LocalBuilder(
             build_func='ndk' if use_android else 'default'),
         runner=autotvm.RPCRunner(
-            device_key, host='fleet', port=9190,
+            device_key, host='localhost', port=9190,
             number=5,
             timeout=10,
         ),

tutorials/autotvm/tune_relay_cuda.py

 """
 Auto-tuning a convolutional network for NVIDIA GPU
-====================================================
+==================================================
 **Author**: `Lianmin Zheng <https://github.com/merrymercy>`_, `Eddie Yan <https://github.com/eqy/>`_
 
 Auto-tuning for specific devices and workloads is critical for getting the

tutorials/autotvm/tune_relay_mobile_gpu.py

 """
 Auto-tuning a convolutional network for Mobile GPU
-====================================================
+==================================================
 **Author**: `Lianmin Zheng <https://https://github.com/merrymercy>`_, `Eddie Yan <https://github.com/eqy>`_
 
 Auto-tuning for a specific device is critical for getting the best

tutorials/autotvm/tune_relay_x86.py

 """
-kuto-tuning a convolutional network for x86 CPU
-====================================================
+Auto-tuning a convolutional network for x86 CPU
+===============================================
 **Author**: `Yao Wang <https://github.com/kevinthesun>`_, `Eddie Yan <https://github.com/eqy>`_
 
 This is a tutorial about how to tune convolution neural network

tutorials/autotvm/tune_nnvm_arm.py → tutorials/nnvm/tune_nnvm_arm.py

 """
-Auto-tuning a convolutional network for ARM CPU
-====================================================
+Auto-tuning a convolutional network for ARM CPU (NNVM)
+======================================================
 **Author**: `Lianmin Zheng <https://github.com/merrymercy>`_, `Zhao Wu <https://github.com/FrozenGene>`_
 
 Auto-tuning for a specific ARM device is critical for getting the best

tutorials/autotvm/tune_nnvm_cuda.py → tutorials/nnvm/tune_nnvm_cuda.py

 """
-Auto-tuning a convolutional network for NVIDIA GPU
-====================================================
+Auto-tuning a convolutional network for NVIDIA GPU (NNVM)
+=========================================================
 **Author**: `Lianmin Zheng <https://https://github.com/merrymercy>`_
 
 Auto-tuning for specific devices and workloads is critical for getting the

tutorials/autotvm/tune_nnvm_mobile_gpu.py → tutorials/nnvm/tune_nnvm_mobile_gpu.py

 """
-Auto-tuning a convolutional network for Mobile GPU
-====================================================
+Auto-tuning a convolutional network for Mobile GPU (NNVM)
+=========================================================
 **Author**: `Lianmin Zheng <https://https://github.com/merrymercy>`_
 
 Auto-tuning for a specific device is critical for getting the best

tutorials/autotvm/tune_nnvm_x86.py → tutorials/nnvm/tune_nnvm_x86.py

 """
-Auto-tuning a convolutional network for x86 CPU
-====================================================
+Auto-tuning a convolutional network for x86 CPU (NNVM)
+======================================================
 **Author**: `Yao Wang <https://github.com/kevinthesun>`_
 
 This is a tutorial about how to tune convolution neural network