Update README.rst
Update README.rst

I believe 'AbstractText' was intended here (as opposed to 'AbstractClass').
divio/djangocms-text-ckeditor,SmithsonianEnterprises/djangocms-text-ckeditor,webu/djangocms-text-ckeditor,alsoicode/djangocms-text-ckeditor,czpython/djangocms-text-ckeditor,divio/djangocms-text-ckeditor,SmithsonianEnterprises/djangocms-text-ckeditor,alsoicode/djangocms-text-ckeditor,webu/djangocms-text-ckeditor,SmithsonianEnterprises/djangocms-text-ckeditor,barseghyanartur/djangocms-text-ckeditor,barseghyanartur/djangocms-text-ckeditor,barseghyanartur/djangocms-text-ckeditor,divio/djangocms-text-ckeditor,webu/djangocms-text-ckeditor,vxsx/djangocms-text-ckeditor,DylannCordel/djangocms-text-ckeditor,vxsx/djangocms-text-ckeditor,alsoicode/djangocms-text-ckeditor,czpython/djangocms-text-ckeditor,yakky/djangocms-text-ckeditor,alsoicode/djangocms-text-ckeditor,vxsx/djangocms-text-ckeditor,yakky/djangocms-text-ckeditor,barseghyanartur/djangocms-text-ckeditor,DylannCordel/djangocms-text-ckeditor,DylannCordel/djangocms-text-ckeditor,czpython/djangocms-text-ckeditor,yakky/djangocms-text-ckeditor,vxsx/djangocms-text-ckeditor,DylannCordel/djangocms-text-ckeditor,SmithsonianEnterprises/djangocms-text-ckeditor,divio/djangocms-text-ckeditor,czpython/djangocms-text-ckeditor,webu/djangocms-text-ckeditor