PMD-PLSQL - derive different faux-filename suffices for package/type specifications and bodies
                     -  Add rules for date
CPD- add getter for list of Source paths
XPATH - make DocumentNavigator more robust
CPD: Rename List<String> getSources() to getSourcePaths()
CPD: add getter for all identified or added Sources
Changed TokenEntry to use ThreadLocal.

Two static fields are now stored in ThreadLocal.  This allows
multiple instances of CPD to run concurrently without stepping
on each other (eg: multi-module Maven projects.)
pmd: use java 8 as default version of java.
pmd-eclipse: Add "PMD" keyword to all preference pages

Otherwise the subpages are not shown when searching for "PMD" in the
preferences.
pmd-eclipse: Support workspace-relative path in ruleSetFile property

When using multiple projects that want to share the rule set definitions
in a single file, it's currently only possible to reference the shared
file using an absolute path. The downside of the absolute path is that
it is different for each developer, so the resulting .pmd file can not
be committed in the repository.

To fix this, this change also tries to resolve the path against the
workspace root, so e.g. "/foo/.ruleset" can be used to refer to the
.ruleset file in the foo project.

Such a path can be ambiguous to an absolute file system path, but in
practice it should not be a problem. An alternative solution would be to
support variables (as known from Eclipse run configurations) such as
"${project_loc:foo}" in the path.
pmd: Improve java 8 parser
pmd: fix unit tests after changing default java version to 1.8.
pmd: add java 8 syntax for type annotations
pmd: adjust variable declarator id for missing type node in case
of lambda expressions.
pmd: add intersectionTypes flag to ASTCastExpression
pmd: add test code that cannot be parsed, but is valid java 8 code.
pmd: enable some ignored tests and remove System.out in tests...
Merge branch 'master' of github.com:sturton/pmd into sturton-master
pmd: register plsql dates ruleset
Merge branch 'cpd_concurrency' of github.com:golpira/pmd into golpira-cpd_concurrency
pmd: update changelog