ClickhouseLZ4OutputStream can override write method with buffer

[azsane]

ClickhouseLZ4OutputStream only implements write method with signature void write(int b)
but caller invokes write(byte[] buffer,int offset,int len) method

default implementation of this method is defined in parent class OutputStream calling write(int b)
hence will copy byte by byte to the currentBlock buffer

override write method and use System.arraycopy should improve peformance

[zhicwu]

Thank you @azsane. It's been merged into develop branch, and it will be part of the upcoming 0.2.6 release.