chore(maven): simplify build (#265)

Stop having bonita-web as parent
  - this added gwt dependencies to all modules
  - use bom for dependencies management instead

remove declaration of uid version as it is not used (confirmed by the version
which relates to bonita 7.6)

upgrade plugins versions to latest available
remove unused plugins
  - checksum-maven-plugin
  - jacoco-maven-plugin

update maven-compiler plugin configuration

Introduce bonita-war to replace all-in-one and war-server
  - the main change is to declare all dependencies in war-server to let maven
  resolve dependencies
  - only on community for now
  - previously, as we copied the lib from the web war and add the one for
  bonita-server, the dependencies resolution could not be properly done by maven
  So, now, just copy web resources first to create the initial war, then add all
  the lib to the war via full maven resolution

Simplify the bundle preparation
  - previously, it was done in several steps because we had the deploy and the
  wildfly bundles.
  - now, we create a 'tomcat distribution for bonita', used for both Community
  and Enterprise to remove duplication

Other changes
  - remove license files
  They are only packaged in the deploy bundle but not in the final tomcat one,
  so remove them
  - remove spnego jar from repository and get it as maven dependency
  - package: avoid warning on windows (outputDirectory)