Merge pull request #2531 from chrisvest/2.0-merge-1.9

2.0 merge 1.9
Prohibit using more than one hint per identifier
Layout fixes for the manual.

* Resize the logo to fix rendering in Firefox.
* Wrap the book title in a separate element for styling.
* Make the version switcher less confusing.
* Default to hide the TOC on smaller screens.
Merge pull request #2558 from nawroth/manual-layout

 Layout fixes for the manual.
Change shortest path planning to use regular cost function
Adding tests for shortestPath
Add support to Ronja for handling nested pattern expressions inside other expressions in RETURN and WITH
Remove shortest path rels from consideration for uniqueness predicates
Add support to Ronja for handling nested pattern expressions inside other expressions in WHERE
Merge branch 2.0-maint into 2.1-maint

Conflicts:
	community/cypher/cypher-compiler-2.0/src/main/scala/org/neo4j/cypher/internal/compiler/v2_0/ast/Clause.scala
	community/cypher/cypher-compiler-2.0/src/main/scala/org/neo4j/cypher/internal/compiler/v2_0/ast/Hint.scala
	community/cypher/cypher/src/test/scala/org/neo4j/cypher/UsingAcceptanceTest.scala
Fix imports for scala style (import scala.Some)
Merge pull request #2572 from systay/2.0-merged-into-2.1

2.0 merged into 2.1
Merge pull request #2570 from boggle/shortest-p

shortest path: regular planning and more tests
Merge pull request #2563 from davidegrohmann/2.1-pattern-expressions

Add support to Ronja for handling nested pattern expressions inside other expressions
Clean up of PlannerQuery and QueryGraph