Renamed IM_ARRAYSIZE() -> IM_COUNTOF(). Kept legacy name for now.

docs/CHANGELOG.txt

@@ -49,6 +49,7 @@ Breaking Changes:
     identifiers using "###", and will allow fixing other dangling issues.
   - This will invalidate hashes (stored in .ini data) for Tables and Windows
     that are using the "###" operators. (#713, #1698)
+- Renamed helper macro IM_ARRAYSIZE() -> IM_COUNTOF(). Kept redirection/legacy name.
 - Fonts: Fixed handling of `ImFontConfig::FontDataOwnedByAtlas = false` which
   did erroneously make a copy of the font data, essentially defeating the purpose
   of this flag and wasting memory (undetected since July 2015 and now spotted

docs/FONTS.md

@@ -202,7 +202,7 @@ if (ImGui::Button(u8"ロード"))
 {
     // do stuff
 }
-ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::InputText("string", buf, IM_COUNTOF(buf));
 ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
 ```
 
@@ -439,7 +439,7 @@ unsigned char* tex_pixels = nullptr;
 int tex_width, tex_height;
 io.Fonts->GetTexDataAsRGBA32(&tex_pixels, &tex_width, &tex_height);
 
-for (int rect_n = 0; rect_n < IM_ARRAYSIZE(rect_ids); rect_n++)
+for (int rect_n = 0; rect_n < IM_COUNTOF(rect_ids); rect_n++)
     if (const ImTextureRect* rect = io.Fonts->GetCustomRect(rect_ids[rect_n]))
     {
         // Fill the custom rectangle with red pixels (in reality you would draw/copy your bitmap data here!)

docs/README.md

@@ -52,7 +52,7 @@ After Dear ImGui is set up in your application, you can use it from \_anywhere\_
 ImGui::Text("Hello, world %d", 123);
 if (ImGui::Button("Save"))
     MySaveFunction();
-ImGui::InputText("string", buf, IM_ARRAYSIZE(buf));
+ImGui::InputText("string", buf, IM_COUNTOF(buf));
 ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
 ```
 ![sample code output (dark, segoeui font, freetype)](https://user-images.githubusercontent.com/8225057/191050833-b7ecf528-bfae-4a9f-ac1b-f3d83437a2f4.png)