Fix Windows unit tests

14 failures at last check (http://qa.nuxeo.org/jenkins/job/nuxeo-master-fullbuild-windows/27/):

• org.nuxeo.ecm.automation.jbpm.test.JbpmAutomationTest.testCreateSeveralTasksChain
• org.nuxeo.ecm.platform.suggestbox.utils.TestDateMatcher.test
• org.nuxeo.ecm.platform.sync.processor.TestXPathUtils.testSetBlobProperties
• org.nuxeo.ecm.core.convert.plugins.tests.TestMailConverter.testTextAndHtmlEmailTransformation (NXP-8540)
• org.nuxeo.ecm.core.convert.plugins.tests.TestMailConverter.testOnlyHtmlEmailTransformation (NXP-8540)
• org.nuxeo.ecm.platform.forms.layout.io.plugins.test.TestLayoutExport.testLayoutDefinitionExport
• org.nuxeo.ecm.platform.filemanager.TestFileManagerService.testCreateNote
• org.nuxeo.ecm.platform.filemanager.TestFileManagerService.testCreateNoteTwiceFromSameBlob
• org.nuxeo.ecm.platform.rendering.test.TestFreemarkerRendering.testRendering
• org.nuxeo.theme.test.themes.TestThemeSerializer.testSerializeTheme
• org.nuxeo.theme.test.html.TestJSUtils.testCompressSource
• org.nuxeo.theme.styling.tests.TestThemeStylingService.testStylesRegistration
• org.nuxeo.theme.styling.tests.TestThemeStylingService.testFlavorsRegistration
• org.nuxeo.theme.styling.tests.TestThemeStylingService.testUnregister