Update bigbluebutton-web to gradle 5.1 (Work In Progress)

bbb-common-web/project/Dependencies.scala

bigbluebutton-web/application.properties

bigbluebutton-web/build.gradle

bigbluebutton-web/gradle.properties

bigbluebutton-web/gradle/wrapper/gradle-wrapper.jar

bigbluebutton-web/gradle/wrapper/gradle-wrapper.properties

bigbluebutton-web/gradlew

bigbluebutton-web/gradlew.bat

...luebutton-web/grails-app/assets/images/advancedgrails.svg

...-web/grails-app/assets/images/apple-touch-icon-retina.png

...ebutton-web/grails-app/assets/images/apple-touch-icon.png

bigbluebutton-web/grails-app/assets/images/documentation.svg

bigbluebutton-web/grails-app/assets/images/favicon.ico

...b/grails-app/assets/images/grails-cupsonly-logo-white.svg

bigbluebutton-web/grails-app/assets/images/grails.svg

bigbluebutton-web/grails-app/assets/images/grails_logo.png

...button-web/grails-app/assets/images/skin/database_add.png

...ton-web/grails-app/assets/images/skin/database_delete.png

...utton-web/grails-app/assets/images/skin/database_edit.png

...utton-web/grails-app/assets/images/skin/database_save.png