Sftp multi tcp stream download with producer and consumer pattern

new file:   src/main/java/org/voyiger/tools/Sftp.java
modified:   src/main/java/org/voyiger/tools/SftpGetThreadPoolHdfs.java
new file:   src/main/java/org/voyiger/tools/SftpGetThreadPoolQueue.java
modified:   src/main/java/org/voyiger/tools/SftpUtils.java
modified:   src/main/java/org/voyiger/util/HDFSUtils.java