Introduce cache.memory_ratio configuration for HPCache

New set-and-forget configuration that specifies cache size as a ratio of the
old generation max size. Memory division across internal components of the cache
is handled by fixed ratios.

If any of the old config (now referred to as "advanced config") is set, it will
override the memory_ratio configuration.
Browser: escape server response to prevent XSS.

Fixes #2139
Java subprocesses that we launch must be headless.

This is necessary for running tests on the build agents. This only
affects 1.9 because that runs against Java 6 where JMX insists on
starting up AWT even when it doesn't need a GUI.
Java subprocesses that we launch must be headless.

This is necessary for running tests on the build agents. This only
affects 1.9 because that runs against Java 6 where JMX insists on
starting up AWT even when it doesn't need a GUI.
Merge pull request #3023 from benbc/1.9-headless

Java subprocesses that we launch must be headless.
Java subprocesses that we launch must be headless.
Don't use exceptions for control flow.
Fix svg preserveAspectRatio attribute value.

* It's case sensitive in some browsers.
Merge remote-tracking branch 'upstream/1.9-maint' into 2.0-maint

Conflicts:
	community/lucene-index/src/test/java/org/neo4j/index/impl/lucene/TestRecovery.java
	enterprise/ha/src/test/java/org/neo4j/ha/TestPullUpdatesApplied.java
Merge pull request #3034 from davidegrohmann/merge-1.9-into-2.0

Merge 1.9 into 2.0
Everything not starting with 'cmdchar' is cypher.

* Also remove old debug message
Fix link
Merge remote-tracking branch 'upstream/2.0-maint' into 2.1-maint
Merge pull request #3035 from davidegrohmann/merge-2.0-into-2.1

Merge 2.0 into 2.1
Merge pull request #3029 from thobe/2.1-null-on-no-index

[2.1] Don't use exceptions for control flow
Prettier exception when backup target is different store
Add semantic checking to unique constraints in AST

This avoids the unnecessary creation of an additional legacy query tree
for every statement.
Merge pull request #3048 from cleishm/no-legacy-verify

Add semantic checking to unique constraints in AST
Merge pull request #3002 from lutovich/2.1-prettier-exception-in-backup

Prettier exception when backup target is different store
Remove artifacts from merge