fixed sql splitting issue

[DuanYuePeng]

Issue 1

for below sql statement, the split function will fail because the table name contains "END".

CREATE TABLE bar (foo VARCHAR(255));
CREATE TABLE gender (gender VARCHAR(255));
CREATE TABLE foo (bar VARCHAR(255));

fixed this issue by checking whether the keywords (END or BEGIN) is separated by any controlling char. eg. '\t', '\n' or ' '.

Issue 2

for below sql statement, the split function will fail because of incorrect inBlockComment flag.

CREATE TABLE bar (foo VARCHAR(255));
/* Insert Values */
INSERT INTO bar (foo) values ('--1');
INSERT INTO bar (foo) values ('--2');

fixed this issue by setting inBlockComment to false after skipping the block comment.

[rnorth]

Thank you @DuanYuePeng - I'll have a look soon.

[rnorth]

I've carried this over to #1627, where I've modified the tests to be more thorough.
@DuanYuePeng thanks for your work on this - it's impressively solid so far!