convert to匹配模式优化，允许两个单词中间有多个空格

	add test cases
	comments use english more understandable

	make cover passed
	make test-cli passed

	string -> int can use index

COL.014 modify the judgment about the character set;COL.012/COL.015 add the judgment about the json type;ALT.001 modify the judgment about the ;fix func ShowCreateTable's error when table is partition;

  remove fmt.Println debug output
  LIT.003 remove varchar, text check for primary key

  WHEN InvisibleUnicode IN SQL give suggestion
  update test cases golden file

  SELECT c1, c2, c3, FROM tb WHERE id < 1000 AND content="mytest* as test"

  update table1 set a = ( select a from table2 where b=1 and c=2) and b=1 where d=2
  update table1 set a = ( select a from table2 where b=1 and c=2), b=1, c=2 where d=2

  replace test-cli percent number with n% for CI

  COL.014 support NVARCHAR
  COL.013 support zero time

- Fix RuleImplicitConversion(ARG.003) with INT and DECIMAL
- Fix RuleImplicitConversion duplicate suggest when use IN () operator

  fix #213 CLA.001 NO WHERE CONDITION
  fix PRIMARY key append to multi column index

  1. update change log
  2. fix ERR parse bug

  col = 1 OR col IS NULL
  col1 = 1 OR col2 = 1

  sleep(), benchmark(), get_lock, release_lock() are
  dangerous function may not be used in online.

  WHERE col = col = '' and col1 = 'xx'

not fix too many connections yet

  RES.009 not consider about "and", "or"... Operator in
  BinaryOperationExpr

  RuleTimePrecision
  MySQL 5.6.4+ New time data type, support time precision to microsecond

  column.Tp may be nil when checking

  bit type not config as int, when two columns compare will
  give ARG.003 suggestion.

  fix #154, #157 by the way