Added the missing 'override' in debug.model
Logical structure works on 2.10

Added a version checker.
Added logical structure tests.
Added methods to the Scala debug model to:
* get handle to objects and classes
* get field value on classes and static classes
* invoke methods on classes and static classes
Avoid race condition in renaming by running on the PC thread.

Fixes #1001381
Merge pull request #256 from misto/misto/issue/rename-race-condition-1001381

Avoid race condition in renaming by running on the PC thread.
Implemented trait for field acces and method invocation
Renamed the wrapped JDI element as 'underlying'
Merge pull request #251 from skyluc/issue/logical-structure-210-1001315

Logical structure works on 2.10
Tweak the tests to workaround defect.

On Linux, additional inaccurate matches are returned in the 2
updated tests (see #1001392).
Tweaked the test data to avoid being in this case.

Fix #1001391
Merge pull request #259 from skyluc/issue/inaccurate-matches-on-linux-1001391

Tweak the tests to workaround defect.
Fixed #1001304 - NSDHO when hovering the Scala launch shortcut

When checking if a runnable JUnit test class is available in the compilation
unit containing the selected code element, it is sometime possible to get a
Scala compiler exception: ``No symbol does not have an owner``. This happens
when trying to access the ``owner`` member of a ``Symbol`` that is of type
``NoSymbol``.

I'm unfortunately not sure on the whys this can happen, but the net result is
particularly bad. The pragmatic solution is to check that the ``symbol`` is a
``ClassSymbol``, and simply bail out when it isn't.

No test is available because we honestly have no clue about how to reproduce
this.
Show Run As > JUnit Test when right clicking on a source that contains runnable
JUnit Test classes

If a source is closed (i.e., it hasn't been typechecked yet - this is
important!) and, through the package explorer, you right click and select Run
As, no "JUnit Test" option used to be shown.

The problem was that if the source is not opened (and typechecked), the
``@Test`` annotation can only be found in the AST, and not in the symbol. The
fix is to always initialize the member's symbol before looking if it declares
the ``@Test`` annotation.  By doing so, the ``@Test`` annotation is found also
for members inherited from a superclass or a trait!

In this commit I've also implemented the missing logic for considering the
JUnit4 ``@RunWith`` annotation. Basically, if a class or any of its inherited
types specify   the ``@RunWith`` annotation, then the class is a valid,
runnable, JUnit4 test class.

As part of this commit I've also made some improvements to the existing testing
class (formerly named ``LaunchableTesters``, now splitted into two distinct
classes: ``MainMethodFinderTest`` and ``RunAsTest``).

The work on these tickets (Re #1001379, Re #1001380) was somewhat motivated by
(or a consequence of) Re #1001304 and Re #1001275.

Finally, I'm quite convinced that the ``ScalaLaunchShortcut.getMainMethods``
could use some similar love, but this should be done in a separate PR(there is
already enough meat here).

Fix #1001234, Fix #1001379, Fix #1001380 and Fix #1000731.
Merge pull request #260 from dotta/issue/NSDHO-1001304

Issue/nsdho 1001304
Implemented JUnit test finder logic in Scala.

Works for both Scala and Java sources, and adds a 'Scala JUnit' test kind and
shortcut for 'Run As'.

Fixed #1001275, Fixed #1000782.