adding two methods to HA GDB Factory that override the behavior of the GDB Factory
Simplified the way separate header is extracted in multi-file case

in the batch importer, where multiple files are seen as one Readable, and
so the header is always extracted from the first line of the data stream.
Although there's still support for getting the header from a completely
different source.
Moved generic option interpretation into Args
Abbreviate common connection closed error.

When the client closes a connection to the server before recieving the full
reply, the server currently prints a lengthy stack trace to the log. This
stack trace is not helpful, because we already do the right thing here.

Replace stack trace with one-line log message noting the client closed the
connection.
Introduce debug capability for request content logging.

Currently undocumented, this introduces experimental support for logging
full request and response bodies. This is currently enabled by setting:

    org.neo4j.server.http.unsafe.content_log.enabled=true

In neo4j-server.properties, and by specifying the http log to output full
requests and responses:

    <pattern>%fullRequest\n\n%fullResponse</pattern>

As this uses mechanisms to fully duplicate incoming request and response
streams, it is strongly recommended to not run this in a production setting.
However, it should prove very useful for debugging and testing.
Fix flay testserverbuilder test.
Improved unnesting of Apply

Instead of using complicated rewrites that tried to remove Apply
in a single step, this rewriter uses many small rewrite steps that
each is very simple to implement and understand. Together
they unnest most plans with Apply in them
Added the concept of input groups in batch importer

where one group consists of one or more files, logically seen as
concatenated by the batch importer. The first line of an input group
defines the header. An import can have multiple node/relationship groups.

For the command line tool this looks something like:

  ./neo4j-import --into path/to/db
                 --nodes file1;file2;file3;...
		 --nodes file4;file5;...
		 --relationships file6;file7;...
		 ...
Merge pull request #3396 from systay/more-unnesting

Improved unnesting of Apply
Merge pull request #3393 from lutovich/merge-2.1-to-master

(2.1)-[:MERGE]->(2.2)
Merge pull request #3384 from tinwelint/2.2-bip-input-multiple-files

BatchImport input multiple files
Merge pull request #3377 from jakewins/2.1-connmsg

Abbreviate common connection closed error.
Merge pull request #3399 from chrisvest/2.1-req-content-logging

Introduce debug capability for request content logging.
Replace `gds#findNodesByLabelAndProperty` with `gds#findNodes`
Replace usage of gds#findNodesBLAP with gds#findNodes
Add gds#findNodes(label)
Replace usage of ggo#getANWL with gds#findNodes
Add gsd#findNode
Merge branch '2.1-maint' into 2.2-merge-2.1

Conflicts:
	community/server/src/main/java/org/neo4j/server/rest/transactional/ExecutionResultSerializer.java
	community/server/src/test/java/org/neo4j/server/rest/transactional/ExecutionResultSerializerTest.java
More concise CSV header format for nodes and relationships

where header entries with semantic data, like node ids, relationship type
and labels must be specified with their corresponding types, no longer
relying in their position in the header. At the same time removed the need
for naming these columns.

Previously some header entries relied on position and some relied on type
being specified.

So, now a node header might look like:
:ID,name,:LABEL,year_of_birth:int

and a relationship header like:
:START_ID,:TYPE,:END_ID,some_property:String