* engine/pom.xml
restore a reference to a (new version of a) necessary servlet library
* pom.xml
remove deprecated {pom.artifactId}; add needed javadoc module version decl
* .classpath
update ref to currently-used servlet jar
* **/pom.xml
bump version identifiers to "3.1.1-SNAPSHOT" (odd minor number meaning dev version, odd patch number indicating expected next patch number of 3.0.x release if before a 3.2.0 release)
* UURIFactoryTest.java
specify stirng literal with escape-encoding, rather than as raw UTF-8
* **/pom.xml
include 'project.build.sourceEncoding' property to suppress platform-encoding warnings
(unfortunately, neither this nor similar 'maven.compile.encoding' property actually casues maven build to interpret Java source as UTF-8)