Refactor HyperlinkClickHandler to cleanup event binding

Move control of event bindings from SessionController to
HyperlinkClickHandler so bindings will be updated whenever modifier is
changed. This allows some simplification as HyperlinkClickHandler can
simply use the KeyboardHandler.Modifier.
Remove unnecessary duplicate click handler in the viewer plugin

The viewer was quite recently modified to use a session controller to
take advantage of the improved selection rendering system. This makes
the manual creation of the hyperlink click manager unnecessary.
Add tooltip support for hyperlink
Enable the hyperlink tooltip in the ODT viewer
Merge pull request #439 from peitschie/hyperlinkTooltip

Add tooltip support for hyperlink
Refactored creation of style tree

Moved the creation of the style tree out of Styles2CSS. This is the first
step in refactoring out and fixing some duplicate list handling code in
OdfCanvas.js.
Refactored application of list styles

Moved the code that parses ODF lists styles and creates rules for them
into a separate object. This is done as the second step in removing
duplicate/redundant code from OdfCanvas.js around some list style
handling.
Implement label-width-and-position mode for list layout

Remove the partial handling of list indentation and implement the default
option for list-level-position-and-space-mode.

http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#property-text_list-level-position-and-space-mode
Implement label-alignment mode for list layout

Add handling for the label-alignment list style element. This commit does
not implement the text:label-followed-by attribute so for now a hard coded
padding has been substituted

http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#__RefHeading__1416522_253892949
Initialise indents and widths to default values

This prevents us from being unable to sum these values together
Remove redundant variables and add further comments
Added some layout tests for list styles

Added one test for label-alignment styling and another test for
label-width-and-position mode