moves Types and Annots to the top-level

I'd love to factor them out into separate files, but since we heavily
rely on sealedness, that's not going to happen
pluralizes module names
Enumerator => Enum, ValueDefiniton => Val
contracts Sequence
renames backquoted fields
upgrades to scala 2.11.0, paradise 2.0.0 and sbt 0.13.2
fixes some minor naming inconsistencies

Our names are quite inconsistent as they are now (we use verbs, nouns
and adjectives all alike), and it's not easily fixed, because some of the
very established names are heterogeneous (compare Select, Assign, Typed
and Extractor). This commit fixes some of the most outstanding wats.
SuperSelect's qual and supertype are types not terms
singularizes module names, evicts the Tree super-object
better names for formerly backquoted fields
Merge pull request #27 from xeno-by/master

busywork to get me into the flow