add toJsonString/fromJsonString
minor improvements
[maven-release-plugin] prepare release time-parent_2.10-2.3
[maven-release-plugin] prepare for next development iteration
better way of formatting/parsing json string
Update README.md
update README
bump version to 2.4
bump version to 2.5-SNAPSHOT
don't add millis in JSON dates

OCPP-J relies on those not being there
bump version to 2.5
bump version to 2.6-SNAPSHOT
use newer Scala parent pom
enable Travis-CI notifications on Slack
update parent pom
Bump deps versions
[maven-release-plugin] prepare release time-parent_2.10-2.6
[maven-release-plugin] prepare for next development iteration
Deployment failed. Revert to 2.6
[maven-release-plugin] prepare release time-parent_2.10-2.6