Add Siddhi as a java user guide
Add Siddhi as a java user guide

wso2/siddhi,dilini-muthumala/siddhi,mohanvive/siddhi,gokul/siddhi,suhothayan/siddhi,gokul/siddhi,tishan89/siddhi,ramindu90/siddhi,ramindu90/siddhi,tishan89/siddhi,mohanvive/siddhi,wso2/siddhi,suhothayan/siddhi,grainier/siddhi,grainier/siddhi,dilini-muthumala/siddhi