Merge branch 'portal_links'

src/main/java/it/inaf/oats/vospace/BaseNodeController.java

src/main/java/it/inaf/oats/vospace/CreateNodeController.java

src/main/java/it/inaf/oats/vospace/FileServiceClient.java

src/main/java/it/inaf/oats/vospace/LinkService.java

src/main/java/it/inaf/oats/vospace/SetNodeController.java

src/main/java/it/inaf/oats/vospace/URIUtils.java

src/main/java/it/inaf/oats/vospace/UriService.java

src/main/java/it/inaf/oats/vospace/persistence/NodeDAO.java

...t/java/it/inaf/oats/vospace/CreateNodeControllerTest.java

...test/java/it/inaf/oats/vospace/FileServiceClientTest.java

src/test/java/it/inaf/oats/vospace/LinkServiceTest.java

src/test/java/it/inaf/oats/vospace/URIUtilsTest.java

src/test/java/it/inaf/oats/vospace/UriServiceTest.java

src/test/resources/create-link-node-external-http.xml

src/test/resources/test-data.sql