Add fixUpInsertion to newFromDocumentReplace

In order to do this we have to separate out the removal
operation from NDFR, so it becomes newFromDocumentInsertion
(again, although actually, for the first time). As NFDI is
an insertion we can just run fixUpInsertion on the data
part of it.

In order for the removal operation to be a proper removal
we have to allow metadata removal (the default is to merge it).

Change-Id: I16d575b61b9796e7e889f2c27cfe02b4a40b7639
Rich paste

Allow pasting of rich (HTML) content.

ve.ce.Surface
* Use a sliced document clone for converting to DM HTML (copy)
* Add full context to pasteTarget before copying
* Add ve-pasteProtect class to spans to prevent them being dropped
* Implement external paste by converting HTML to data and inserting
  with newFromDocumentInsertion
* Remove clipboard key placeholder after read so they aren't picked
  up by rich paste. Hash no longer includes the placeholder.
* Detect the corruption of important spans and fallback to clipboard
  data HTML if available.

ve.dm.LinearData
* Add clone method for copy

ve.dm.ElementLinearData
* Add compareUnannotated for use by context diffing.
* Add sanitize method for cleaning data according to a set of rules.

ve.dm.Transaction
* Add range parameter for inserting a range of a document only,
  e.g. stripping the paste context.

ve.dm.Document
* Implement sliced document clone creation so that DM HTML
  is generated correctly in onCopy

ve.dm.DocumentSlice
* Replaces LinearDataSlice. Now has two ranges for balanced data
  and data with a full context.

ve.init.Target.js
* Define default, loose, paste rules (just remove aliens).

ve.init.mw.ViewPageTarget
* Define strict MW paste rules:
  + no links, spans, underlines
  + no images, divs, aliens
  + strip extra HTML attribues

ve.init.sa.Target, ve.init.mw.ViewPageTarget, ve.ui.Surface
* Pass through and store paste rules.

Bug: 41193
Bug: 48170
Bug: 50128
Bug: 53828
Change-Id: I38d63e31ee3e3ee11707e3fffed5174e1d633b42
Use rare unicode characters for paste placeholders

Helps with bug reporting, like the snowman and pawn.

Change-Id: Id133431eea987442c8b50a05821ebd54649b26b9
Plain text paste with paste special

Register ctrl/cmd+shift+v as a trigger which sets a flag for the
next paste event.

When the paste special flag is set, modify the sanitizeData method
to strip all annotations, and any elements other than paragraphs.

Bug: 53781
Change-Id: If814e1786ffa805b52ab32f4a06f52da743fd9af
Merge changes If814e178,Id133431e,I38d63e31,I16d575b6

* changes:
  Plain text paste with paste special
  Use rare unicode characters for paste placeholders
  Rich paste
  Add fixUpInsertion to newFromDocumentReplace