[maven-release-plugin] copy for tag engine.io-client-0.6.0

[maven-release-plugin] copy for tag engine.io-client-0.5.1

[maven-release-plugin] copy for tag engine.io-client-0.5.0

[maven-release-plugin] copy for tag engine.io-client-0.4.1

[maven-release-plugin] copy for tag engine.io-client-0.4.0

[maven-release-plugin] copy for tag engine.io-client-0.3.1

[maven-release-plugin] copy for tag engine.io-client-0.3.0

Release 0.2.3

[maven-release-plugin] copy for tag engine.io-client-0.2.2

[maven-release-plugin] copy for tag engine.io-client-0.2.1