README changed to correct markdown
Functions for editing rows added

New POST function on /edit url is added. It handles row ID and
color value, checks if it is in the list and then rewrite old
row with new value.
"Edit row" button added to the row scheme
Edit url added to urls list
"Edit row" function added to tedit plugin

Function "Edit row" changes table's row to edit mode and then sends
changed value to server.
It's pretty similar to "Add row" function.