#291 display-dependency-updates: introduce switch processDependencyManagementTransitive

[stefanseifert]

adding a new switch processDependencyManagementTransitive to display-dependency-updates goal, with same semantics as it was added with #129 to dependency-update-report

the default value is true which reflects the current behavior (backward compatibility).

if set to false, the dependency check is done using the "original model", meaning dependencies with "import" scope (often called "BOM") are not interpolated and checked itself, instead of the transitive dependencies they import (over which the user has no direct control).

please note: this works as described if the BOM import dependency is declared in the current POM. if such a dependency is declared in the parent POM, it works a bit different: if the current POM references dependencies declared in the POM references in the parent POM, the versions updates of those dependencies are reported, not of the BOM itself. still, with this new feature working with huge lists of transitive dependencies from BOMs gets much easier.

Fixes #291