Moved askReload calls to the Eclipse reconciler mechanism.

You can now register files for reloading in ScalaPresentationCompiler.scheduleReload
They are flushed at reconciliation, and reconciliation updates the error annotations

Fixing indentation.
proper structure for ErrorAnnotation update
Plugs in IJavaReconcilingListeners

Better interfaces
Essential tweaks in Problem annotation safety
Narrows down invalidated text region
Fix stale / ill-formatted code.

Fixes #1001454
De-activated test requiring ui
Fixed ``SemanticHighlightingPositionsTest``

With the new reconciliation strategy implementation, compilation units are not
reloaded by the presentation compiler at every buffer change. Hence, in the
semantic highlighting positions tests, we need to manually force the reload of
the unit after its content is changed, or the tests will fail because the
semantic highlighting reconciler would be performed on the old unit's content.

Reload the unit after its content is replaced
Normalises w.r.t deprecation and namespaces

reloads before interactive demands

adressing PR comments

cosmetics
constrains optimistic cast in ScalaReconciliationStrategy

more eager initialReconcile