Ignored test for #1631: Improve compiler speed for "Hello World" projects

Useful for benchmarking
ClassTransformer: make shortcut refinement trees have implicit tree annotations actual/shared
Add new finer benchmark categories #1631: Improve compiler speed for "Hello World" projects
Fix for #1631: Avoid completing packages just to test for their existence

Much cheaper to not complete them and lazy-complete class files on demand
JavacUtil #1631: faster annotation lookup
Model loader #1631: lazy-load actual/refinedDeclaration because they are expensive and rarely used
Model loader: remove dead code
CompilerTest: the ceylon-spec project actually compiles to bin
Test and updated test .src now that shortcut refinements have proper actual/shared annotations
Updated model loader test for error that will now only be shown when using the actual refined declaration