Dev

* [Update] udpate version to 1.5.6

* [update] add web database support

* [Update] update elfinder version

Create LICENSE

[bugfix] pause and resume WinSize

[Update] web sftp support asset

[Bugfix] fix chinese word search

[Update] remove org name

[Update] update go-elastic to v6

* [Update] update db log info

* [Update] support mysql session

* [update] add db name

* [Update] add mysql-client

[Bugfix] fix regex or no system user panic err

[Bugfix] web sftp path bugs

[Update] fix web sftp

[Bugfix] update elfinder version to fix folder tree

[Bugfix] fix s3 config panic error

[Update] 增加create session参数

[Bugfix] fix telnet login regex panic err

[bugifx] support old ssh key algorithms

 sftp node tree

Dev

Update version to 1.5.5

[Update] add done chan to prevent from blocking