package library for extended_image, extended_text and extended_text_field, provide common base class.
extended official image to support placeholder(loading)/ failed state, cache network,zoom/pan,photo view,crop,save,clip,paint custom etc
extended official text to quickly build special text like inline image or @somebody,it also provide custom background,custom over flow.
extended official text field to quickly build special text like inline image or @somebody etc.