[quick] Space should commit first candidate if less than one page

This fixes bug #19
Add Chinese frequency list and generating tools, read README in /words for info
Update README
Replace perl+sed with python in countfreq.sh, performance increased from 1m8s to 43s running-time.But memory usage is very high when huge file is used (>20GB ram + swap).Will be fix later.
Update countfreq.sh and the words database
Add new frequency table
Add frequency.csv for later use, it was generated by sed s/ /, /g frequency.txt >frequency.csv
Update README