Rewrite Float commands in Latex3 and move them to new Floats package.

packages/Layout.sty

@@ -95,11 +95,6 @@
 % N.B.: floatpagefraction MUST be less than topfraction !!
 \renewcommand{\dblfloatpagefraction}{0.8}	% require fuller float pages
 
-% Line-breaking zero-width space
-\NewDocumentCommand{\zws}{}{\hspace{0pt}}
-% Line-breaking dot
-\NewDocumentCommand{\bdot}{}{.\zws}
-
 \NewDocumentEnvironment{SmartAdjustWidth}{O{\boolean{isElectronic}} m m +b}{%
 	\ifthenelse{#1}{%
 		\begin{adjustwidth}{#2}{#3}%
@@ -112,43 +107,6 @@
 	}%
 }{}
 
-\newcommand{\bigfloatoffsetratio}{2.0}
-
-% Maximum width adjustment to fit 2 16x9 screensots on one page.
-\ProvideLength{\bigfloatoverhang}[0.54in]
-\newcommand{\bigfloatplacement}{htpb}
-
-\floatstyle{plain}
-\newfloat{generic}{htpb}{lgf}
-
-\NewDocumentEnvironment{BigFloat}{
-	% #1: Float type
-	O{generic}
-	% #2: Overhang: the distance that the BigFloat extends into the margins.
-	O{\bigfloatoverhang} 
-	% #3: Float position: where the float may appear on the page.
-	O{\bigfloatplacement} 
-	% #4: Offset: the ratio between the overhangs on the inside and outside of 
-	%     BigFloat.
-	O{\bigfloatoffsetratio} 
-	% #5: Body: what appears in the BigFloat.
-	+b
-}{%
-	\begin{#1}[#3]% float environment
-		\begin{SmartAdjustWidth}{-#2}{-#2 * \real{#4}}% adjustwidth(*)
-			\begin{minipage}{\linewidth}%{#2 * (#4 + 1) + \textwidth}%
-				\ifthenelse{\boolean{isDraft}}{%
-					{\color{layout}\rule{\textwidth}{1pt}\zws}%
-					#5%
-					%{\color{layout}\rule{\textwidth}{1pt}}%
-				}{%
-					#5%
-				}%
-			\end{minipage}%
-		\end{SmartAdjustWidth}%
-	\end{#1}%
-}{}
-
 \AtBeginDocument{
 	\ifthenelse{\boolean{isElectronic}}{
 		\newgeometry{
@@ -181,11 +139,14 @@
 	}
 	\restoregeometry
 
+	\ExplSyntaxOn
 	\NewDocumentEnvironment{SmallMargin}{O{0.0in} O{-0.25in}}{
 		\clearpage
 		\loadgeometry{smallMargin}
-		\setlength{\insideheaderoffset}{#1}
-		\setlength{\outsideheaderoffset}{#2}
+		\setlength{\HeaderInsideOffset}{#1}
+		%\dim_set:Nn \g_header_insideoffset_dim {#1}
+		\setlength{\HeaderOutsideOffset}{#2}
+		%\dim_set:Nn \g_header_outsideoffset_dim {#2}
 		\pagestyle{fancy}
 	}{
 		\clearpage