task increaseBuildNumber(type: Exec) {
    def versionPropsFile = file('version.properties')
    if (versionPropsFile.canRead()) {
        Properties versionProps = new Properties()

        versionProps.load(new FileInputStream(versionPropsFile))
        def newBuildNumber = versionProps['buildNumber'].toInteger() + 1
        versionProps['buildNumber'] = newBuildNumber.toString()
        versionProps.store(versionPropsFile.newWriter(), null)
    } else {
        throw new GradleException("Could not read version.properties!")
    }
}