bug fix #4298:ImportCSV options UI validation includes "Columns separated with" allows string while "Columns enclosed with" and "Columns escaped with" allow to enter just one character

Signed-off-by: Smita Kumari <kumarismita62@gmail.com>
bug fix #4298: added javascript allow just one character if first character is not escape character else allow two including escape character

Signed-off-by: Smita Kumari <kumarismita62@gmail.com>
unbinding keyup event

Signed-off-by: Smita Kumari <kumarismita62@gmail.com>
Merge pull request #966 from smita786/QA_4_1

bug fix #4298:ImportCSV options UI validation includes "Columns separate...