Many NPEs logged as ERROR when project.basedir is not set

Essentials logs many NullPointerExceptions when the 'project.basedir' environment variable is not set. Instead the Essentials UI should simply show an error message saying 'project.basedir' is needed for Essentials to function. It should still be possible to run the project, view the site and use the CMS without having 'project.basedir' set.

Steps to reproduce:
1. in the root pom.xml of the archetype, comment the line '<project.basedir>${project.basedir}</project.basedir>'

2. start the project with 'mvn -Pcargo.run -Drepo.path=storage'

Expected: no errors in the logs
The following error keep being logged many times:

24.04.2015 15:40:06 ERROR http-nio-8080-exec-9 [AbstractFaultChainInitiatorObserver.onMessage:115] Error occurred during error handling, give up!
org.apache.cxf.interceptor.Fault
at org.apache.cxf.service.invoker.AbstractInvoker.createFault(AbstractInvoker.java:163)
at org.apache.cxf.service.invoker.AbstractInvoker.invoke(AbstractInvoker.java:129)
at org.apache.cxf.jaxrs.JAXRSInvoker.invoke(JAXRSInvoker.java:200)
at org.apache.cxf.jaxrs.JAXRSInvoker.invoke(JAXRSInvoker.java:99)
at org.apache.cxf.interceptor.ServiceInvokerInterceptor$1.run(ServiceInvokerInterceptor.java:59)
at org.apache.cxf.interceptor.ServiceInvokerInterceptor.handleMessage(ServiceInvokerInterceptor.java:96)
at org.apache.cxf.phase.PhaseInterceptorChain.doIntercept(PhaseInterceptorChain.java:307)
at org.apache.cxf.transport.ChainInitiationObserver.onMessage(ChainInitiationObserver.java:121)
at org.apache.cxf.transport.http.AbstractHTTPDestination.invoke(AbstractHTTPDestination.java:251)
at org.apache.cxf.transport.servlet.ServletController.invokeDestination(ServletController.java:223)
at org.apache.cxf.transport.servlet.ServletController.invoke(ServletController.java:197)
at org.apache.cxf.transport.servlet.ServletController.invoke(ServletController.java:149)
at org.apache.cxf.transport.servlet.CXFNonSpringServlet.invoke(CXFNonSpringServlet.java:171)
at org.apache.cxf.transport.servlet.AbstractHTTPServlet.handleRequest(AbstractHTTPServlet.java:290)
at org.apache.cxf.transport.servlet.AbstractHTTPServlet.doGet(AbstractHTTPServlet.java:214)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
at org.apache.cxf.transport.servlet.AbstractHTTPServlet.service(AbstractHTTPServlet.java:265)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.__invoke(StandardContextValve.java:106)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.__invoke(StandardHostValve.java:142)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1517)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1474)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
at org.onehippo.cms7.essentials.plugin.PluginStore.getAllPlugins(PluginStore.java:131)
at org.onehippo.cms7.essentials.plugin.PluginStore.populateSystemInfo(PluginStore.java:180)
at org.onehippo.cms7.essentials.rest.ProjectResource.ping(ProjectResource.java:96)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.apache.cxf.service.invoker.AbstractInvoker.performInvocation(AbstractInvoker.java:181)
at org.apache.cxf.service.invoker.AbstractInvoker.invoke(AbstractInvoker.java:97)
... 39 more