Added comment about TextUnformatted(). (#1450)

imgui.h

@@ -258,7 +258,7 @@ namespace ImGui
     IMGUI_API ImGuiID       GetID(const void* ptr_id);
 
     // Widgets: Text
-    IMGUI_API void          TextUnformatted(const char* text, const char* text_end = NULL);               // doesn't require null terminated string if 'text_end' is specified. no copy done, no limits, recommended for long chunks of text
+    IMGUI_API void          TextUnformatted(const char* text, const char* text_end = NULL);               // raw text without formatting. Roughly equivalent to Text("%s", text) but: A) doesn't require null terminated string if 'text_end' is specified, B) it's faster, no memory copy is done, no buffer size limits, recommended for long chunks of text.
     IMGUI_API void          Text(const char* fmt, ...)                                     IM_FMTARGS(1); // simple formatted text
     IMGUI_API void          TextV(const char* fmt, va_list args)                           IM_FMTLIST(1);
     IMGUI_API void          TextColored(const ImVec4& col, const char* fmt, ...)           IM_FMTARGS(2); // shortcut for PushStyleColor(ImGuiCol_Text, col); Text(fmt, ...); PopStyleColor();