cli: add exec rule to compute precache on mvn compile
cli: add exec rule to compute precache on mvn compile

Patch adds rules in maven to create precached file using cachegen

Signed-off-by: Rohit Yadav <0fa72ca37c4b5fa62675187ce32ea6c9f842fd52@apache.org>

remibergsma/cloudstack-cloudmonkey,apache/cloudstack-cloudmonkey,Interoute/cloudmonkey-interoute,remibergsma/cloudstack-cloudmonkey,Interoute/cloudmonkey-interoute,apache/cloudstack-cloudmonkey