Shell: save history in home dir. Closes #1395.

Specifically, $PWD/.shell_history is now ~/.neo4j_shell_history.
Stable iterators for DiffSets.
Add tests around use of CopyOnWriterAfterIterationHashSet
Revert fix to MergeNodeAction now that the underlying cause has been fixed in kernel
Fixed critical Browser bugs for Internet Explorer

* Updated Angular.js to 1.2.4
* Updated Codemirror
* Fixed overflow bugs on SVG canvas
* Added upgrade splash for IE < 9

fix(browser): overflow hidden on svg elements make IE10 display visualisations better

chore(browser): update to Angular 1.2.3. Animations are still broken

fix(browser): use correct styling directive for legend. Fixes problem in IE10 where they didn't show

Fixes IE not expanding rendered frames to full height

Fix animating frame on enter

Fix for nested .animate() not being triggered

Fixes positioning of frame actions

Added upgrade splash for internet explorer < 9

Fixed drag n' drop for Angular 1.2

Remove console.log in FileUpload directive

Fix editor in IE by upgrading Codemirror

Fix multi-line mode

Focus editor the right way when clicking editor area

Fixed tooltip visibility

Put max height on label color legend

Fix animations

Fcous editor on load

Initialize cursor properly in IE

Fixed drawer animations

Fixed error bar animation

Fix problem when inspector content didn't load + update Angular to 1.2.4
Introduces snapshotting of cluster contexts.

o All context implementations now are able to create snapshots of themselves.
o Implementation does not use clone, to allow passing in service classes to the
  snapshot (services like logging should not be snapshotted).
o All context impl classes have been moved out from being inner classes to living
  in a common package under the multipaxos package.
o Resolved circular dependency between timeouts and state machines.
o Refactored ProtocolServerFactory to allow using it to assemble infrastructure for
  snapshotted state machines.
o Added equals methods to all stateful objects used during runtime by clustering.
o Refactored MultiPaxosContext to be explicit about which state is shared and required
  for which contexts.
Introduces initial work on cluster correctness proover.

o This exhausts all possible cluster delivery orders, generating
  a graph of all possible state transitions the cluster can make.
  Incorrect end states and bad loops can then be inferred from the
  graph and corrected.
Formattting fix for shell docs.
Add some acceptance tests of profiling OPTIONAL MATCH, MERGE and UNION queries
Merge pull request #1693 from boggle/2.0.1-cow-diff-sets

[AFTER GA] 2.0.1 cow diff sets
Update angular reference.
Edit files with Notepad if Desktop.edit fails

The previous code, with its clever use of rundll32 url.dll,FileProtocolHandler is not robust across various versions of Windows.
traversal for constant direction

Implementing a PathExpander ensuring that relationship direction will be constant along the path.
The first relationship determines the direction to follow for all subsequent steps.
Relates to http://stackoverflow.com/questions/20654988/directed-paths-in-neo4j
applying codestyle
tidying up and fixing tests
tidying up and fixing tests
added "node_labels" to root db discovery
Merge pull request #1740 from sarmbruster/constant_direction_expander

traversal for constant direction
Merge pull request #1741 from tinwelint/2.0-reject-prepare-fix

Fixes two clustering issues causing temporary or permanent absence of master
Merge pull request #1726 from jotomo/shell-history-to-home-dir

Shell: save history in home dir. Closes #1395.