sql_tokenize: various improvements
sql_tokenize: various improvements

- drop the use_qident param, wrong place for it
- support multi-symbol operators
- support >2 parts in names
- drop the magic escaping in pynew,pyold.  it does not make sense
- let all unknown symbols count as error

tarvip/skytools,overdrive3000/skytools,tarvip/skytools,overdrive3000/skytools,markokr/skytools,markokr/skytools,overdrive3000/skytools,markokr/skytools,tarvip/skytools