openshift-java-client: improve how userAgent is passed to UrlConnectionClient

public UrlConnectionHttpClient(String username, String password, String userAgent, boolean sslChecks, IMediaType requestMediaType, String acceptedMediaType, String version, String authKey, String authIV) {

public void setUserAgent(String userAgent) {
	this.userAgent = userAgent;
}

public RestService(String baseUrl, String clientId, IHttpClient client) {
	this.baseUrl = UrlUtils.ensureStartsWithHttps(baseUrl);
	this.client = client;
	client.setUserAgent(new RestServiceProperties().getUseragent(clientId));

public IOpenShiftConnection getConnection(final String clientId, final String login, final String password,
		final String authKey, final String authIV, final String serverUrl,
		final boolean proxySet, final String proxyHost, final String proxyPort) throws OpenShiftException {
	Assert.notNull(clientId);
	Assert.notNull(login);
	Assert.notNull(password);
	Assert.notNull(serverUrl);
	
	if (proxySet) {
		System.setProperty("proxyHost", proxyHost);
		System.setProperty("proxyPort", proxyPort);
	}

	try {
		final IHttpClient httpClient = new UrlConnectionHttpClientBuilder().setCredentials(login, password, authKey, authIV)
				.client();
		
		final IRestService service = new RestService(serverUrl, clientId, httpClient);
		return getConnection(service, login, password);
	} catch (FileNotFoundException e) {
		throw new OpenShiftException(e, "Failed to establish connection for user ''{0}}''", login);
	} catch (IOException e) {
		throw new OpenShiftException(e, "Failed to establish connection for user ''{0}}''", login);
	}
}