Support for parameterised queries

[roborourke]

Hi, thanks for publishing this library, it looks really promising and straightforward to use.

I currently have an implementation using the HTTP interface which lets me do parameterised queries like so:

# query not URL encoded for ease of reading
http://localhost:8123/?query=select * from t where event_type = {type:String};&param_type=click

Would it be possible to introduce this feature? I know there are encoding functions but it would be good to make ClickHouse do the work, I'm just not sure how.

Possible interface:

$client->query( 'select * from t where event_type = {type:String}', [
    'type' => 'click',
] )

[lizhichao]

Good idea. I have time to see how to add this feature