add user manual in app instead of pdf

src/node_image.h

@@ -11,6 +11,7 @@ public:
     static Sampler m_sampler_mips;
     bool m_use_atlas = false;
     bool m_use_mipmaps = false;
+    bool m_autosize = false;
     glm::vec4 m_region;
     glm::vec2 m_off;
     glm::vec2 m_sz;