formatting popup design work
Fix BL-176, books would not auto-update when national lang is changed

This will only work for new books or books that have undergone an
"update book" command.

The jade mixins make use of this; existing xmatter pages will need to
be re-compiled from jade to get the changes.
Allow user to choose (No Topic)
Paint checkmarks on dropdown menus in Linux (BL-509)

On Windows, we use a custom renderer to prevent an errant white line,
but on Linux, this renderer prevents the checkmarks from painting.
Remove IDisposable from NaturalSortComparer

There is no reason that NaturalSortComparer should implement
IDisposable - it doesn't deal with unamanged objects or other
objects implement IDisposable. Having it derive from IDisposable
requires us to call the Dispose() method if we want to follow
best practices.
Merge pull request #76 from andrew-polk/BL509_ShowChecksLinux

Paint checkmarks on dropdown menus in Linux (BL-509)
Merge pull request #75 from gmartin7/BL-644AllowNoTopic

Allow user to choose (No Topic)
Merge pull request #77 from ermshiperete/IDisposable

Remove IDisposable from NaturalSortComparer
Disable L10NSharp dialog in Linux (BL-655)
Merge pull request #78 from andrew-polk/BL655_DisableLinuxL10NSharp

Disable L10NSharp dialog in Linux (BL-655)
Rework style dialog and add bold/italic/underline/center

Also makes background color a setting independent of border,
hides style create controls until the user clicks a link,
adds a Create button to immediately create a new style,
allows non-leading numbers in style name,
and gives instructions when bad chars typed.
Merge pull request #74 from BloomBooks/BL-176_ChangeToNationalLang

Bl176 update xmatter fields when user changes national language of the collection
Merge pull request #79 from JohnThomson/moreTab

Rework style dialog and add bold/italic/underline/center