Fixes linter warnings.
Merge pull request #31 from huitseeker/small-cleanups

Fixes linter warnings.
Speeds up find(AllBindings|AllTreesWithSamePosition|SymbolForImportSelector)

cosmetics
fixes #1001905
Merge pull request #32 from huitseeker/speedy-pimps

Speeds up find(AllBindings|AllTreesWithSamePosition|SymbolForImportSelector)
Slightly improved pretty printing of Blocks.

This benefits Extract Method and similar refactorings.
Simplifies expandSymbol() post 2.10

- opacity of positions for synthetics in pattern matching or deconstructing is fixed.
  Besides, Same positions are now > 3 hops away, and not being reported.
- allOverridenSymbols usage
Merge pull request #33 from huitseeker/cleanerExpansion

Simplifies expandSymbol() post 2.10