custom Ember textarea component that accepts dropping files

[emad-elsaid]

the normal textarea doesn't accept drag-n-drop, a custom textarea component should be created to be shared among all tools.

the textarea should have the same interface currently ember has in addition to the following features :

• when a user drag a file over it it should show an indicator that he can drop the file here
• when user drops the file it should read it and fill the textarea with its contents if possible
• add clipboard actions as a toolbar copy-cut-paste
• select all icon to select all textarea contents

the first design suggestion is to enhance the current ember textarea component with the required features. another design is to create a separate component devtools-textarea with the same interface in addition to the required features.

[AmrEldib]

Maybe it should also have "Select All", "Copy" and "Paste". This will be helpful in tools like minify and encoding tools.

[emad-elsaid]

i modified the original issue to include clipboard actions and select all action.