Store directory per indexing test

Windows is at risk of file locking if two tests are running on the same store, or there's a leftover process from a test locking Lucene files.
Imports and some code style
Adds a manual section about the neo4j-shell '-config' option
Fix CypherDocIT breakage cause by changed Cypher semantics

o This is about x.foo now being null if x.foo is not defined on x and
  x.foo? and x.bar! having been removed
More work preparing the experimental parser

o Now accepts patterns with properties without parentheses
o Now accepts CREATE/DROP CONSTRAINT
o Solves problem with named variable length paths that use relationship collections