method two for resend function

Signed-off-by: liuyao <lygoesstraight@163.com>
add .gitignore
Merge branch 'master' into liuyao_new
Revert "method two for resend function"

This reverts commit 77e830f061a86163dc754d681184d936c5913d7f.
add closeAndTimeOutRedeliver function 

Signed-off-by: liuyao <lygoesstraight@163.com>
modify data type of lastCheckTime to long

Signed-off-by: liuyao <lygoesstraight@163.com>
separate timeout resend thread from normal message deliver thread

Signed-off-by: liuyao <lygoesstraight@163.com>