Refactor log handling

CONFIGURATION.md

...rg/openepics/names/rest/controller/ConvertController.java

.../org/openepics/names/rest/controller/NamesController.java

...openepics/names/rest/controller/StructuresController.java

src/main/java/org/openepics/names/service/LogService.java

src/main/java/org/openepics/names/service/MailService.java

src/main/java/org/openepics/names/util/ValidateUtil.java

src/main/resources/application.properties

src/test/java/org/openepics/names/util/ValidateUtilTest.java

src/test/resources/application.properties