Simplify project structure

- harmonize module and directory names
- optimize Gradle settings
- remove unused Grails sample

Resolves: #1447

spring-session-samples/gradle/dependency-management.gradle

@@ -0,0 +1,19 @@
+dependencyManagement {
+	dependencies {
+		dependency 'ch.qos.logback:logback-classic:1.2.3'
+		dependency 'com.maxmind.geoip2:geoip2:2.3.1'
+		dependency 'javax.servlet.jsp.jstl:javax.servlet.jsp.jstl-api:1.2.1'
+		dependency 'javax.servlet.jsp:javax.servlet.jsp-api:2.3.2-b02'
+		dependency 'org.apache.taglibs:taglibs-standard-jstlel:1.2.5'
+		dependency 'org.seleniumhq.selenium:htmlunit-driver:2.32.0'
+		dependency 'org.slf4j:jcl-over-slf4j:1.7.25'
+		dependency 'org.slf4j:log4j-over-slf4j:1.7.25'
+		dependency 'org.webjars:bootstrap:2.3.2'
+		dependency 'org.webjars:html5shiv:3.7.3'
+		dependency 'org.webjars:jquery:1.12.4'
+		dependency 'org.webjars:knockout:2.3.0'
+		dependency 'org.webjars:sockjs-client:0.3.4'
+		dependency 'org.webjars:stomp-websocket:2.3.0'
+		dependency 'org.webjars:webjars-taglib:0.3'
+	}
+}