update readme
update readme

- add note for users having http authentication issues
- add donation link

eekboom/gerrit-intellij-plugin,sstafford/gerrit-rest-java-client,uwolfer/gerrit-intellij-plugin,vogellacompany/gerrit-rest-java-client,uwolfer/gerrit-rest-java-client,vogellacompany/gerrit-rest-java-client,sstafford/gerrit-rest-java-client,uwolfer/gerrit-rest-java-client