Adding missing operators header [ci skip]
add $context->headersManager->add('kernel/operators');

Signed-off-by: Rack Lin <racklin@gmail.com>
Improving trim/ltrim/rtrim supports charlist parameter .

Signed-off-by: Rack Lin <racklin@gmail.com>
Merge remote-tracking branch 'upstream/master'
Merge branch 'bugfix/subpos'
Merge branch 'enhancement/trim_support_2param'
rebuild
Signed-off-by: Rack Lin <racklin@gmail.com>