Fixed doc typo

.github/issue_template.md

@@ -40,6 +40,7 @@ You might select multiple topics, delete the rest:
 **Installation mode**: CMake, sh script, manual Makefile installation, ... (Ubuntu); VS2015, VS2017, CMake, ... (Windows); ...?
 **CUDA version** (`cat /usr/local/cuda/version.txt` in most cases):
 **cuDNN version**:
+**CMake version** (`cmake --version` in Ubuntu):
 **Release or Debug mode**? (by defualt: release):
 **3-D Reconstruction module added**? (by default: no):
 **GPU model** (`nvidia-smi` in Ubuntu):

doc/library_introduction.md

@@ -3,7 +3,7 @@ OpenPose C++ API - Introduction
 
 The C++ API is ideal if you want to e.g. change internal functions and/or extend the OpenPose functionality. In order to learn the basics:
 
-1. Take a look at the [Demo](../README#demo) and [OpenPose Wrapper](../README#openpose-wrapper) sections from the README.
+1. Take a look at the [library Quick Start section](../README#quick-start) from the README.
 2. OpenPose Overview: Learn the basics about the library source code in [doc/library_overview.md](./library_overview.md).
 3. Extending Functionality: Learn how to extend the library in [doc/library_extend_functionality.md](./library_extend_functionality.md).
 4. Adding An Extra Module: Learn how to add an extra module in [doc/library_add_new_module.md](./library_add_new_module.md).