Makes it possible to disable UDC through System property.

This change also makes UDC not fail if an invalid configuration
value is given, instead it interperts it as the default value.
Remove silly shadow
Indent lists
Fix indent for unordered lists as well
Merge pull request #2876 from davidegrohmann/2.2-fix-muninn-shutdown-races

Fix races on shutdown in Muninn
re-introduce border on code blocks
fix missing fluid container on delete help
Increase line-height for bullets in help
Use same line-height for paragraphs
Remove println
Ensure nodes of argument relationships are planned correctly

Simplified examples (assumes no squashing):

o MATCH (a)-[r]-(b) WITH r MATCH (p)-[r]-(q) needs to project p, q from r
o MATCH (p)-[r]-(q) WITH p AS a, q AS b, r MATCH (a)-[r]-(b) needs to filter out r where a, b are not start and end nodes resp.
Rename UnwindPlan => UnwindCollection
Introduce ProjectEndpoints plan and pipe

o Introduce QueryContext.relationship(Start|End)Node
o Tests for ProjectEndpointsPipe
Fix fullscreen mode and get rid of buggy scrollbars
Align styling options better in footer
Replace planArgumentRelEndpoints with newly introduced projectEndpoints step
Merge pull request #2873 from jotomo/milliseconds-timeout

Document time unit used for timeout in javadoc.
Merge pull request #2827 from Archytaus/master

Updated PID file location to come from configuration
Introduce #expand() in the Kernel API

Add a first primitive to the kernel api that uses the
cursor/register spec to define its signature. This first primitive is capable
of expanding a single hop from one source node, and filters by reltype and
direction.

This commit contains:

- A revised Cursor, no longer inheriting from IOCursor as the two perform
  different jobs.
- Register implementations needed for this first primitive.
- A complete "augment" cursor that can overlay local tx state on top of another
  traverse cursor.
- A temporary implementation of a store expand cursor which simply piggybacks
  on existing listRels and visitRel mechanisms in the cache layer.

Next steps:

- Refactor the store format into stand-alone classes, separate from the stores
- Implement a store expand cursor that uses those format classes directly,
  bypassing the cache.
Merge pull request #2875 from boggle/rel-endpoint-circus

Rel endpoint circus