add window locking parameter so that splitting of windows locks together the children for scroll/zoom.

tried several different containers and several different ways to make the frame wider to give a better focus feedback, all to no avail, sigh.

change highlight func to work on canvas items, rationalise highlighting and make work for complex objects, change code handling features to use quarks and new feature calls, add box around introns, add single hash for feature to item mapping, correct off by one bug in intron coords, add menu code for button 3.

add function to find canvas items from their feature description, change scroll to work on an item, add functions to manage feature to item hash.

Add hash for feature to item link, add default background etc. colours, remove redundant focus fields.

Add some default colours for background etc., replace strings with quarks, add box types for feature items, remove redundant focus fields, add calls to manage feature to item hash.

change code to use quarks, not strings, introduce original vs. unique strings for features and sets.

swop up/down strand to forward/reverse, swop strings for quarks, use the new quark related feature calls.