[v5.10.x] Update change log documentation

Change scripts to compatible with jenkins process

Delete unwanted files

[v5.10.x] Adjust README documentation

[v5.7.x] Add change log documentation and contributor guide

Update README and change log documentation

Align Docker Compose resources with WSO2 Software License

Add change log

Fix Mysql jar download URL

[v5.8.x] Update the change log documentation