Add Hakyll site generator and assets

Add site executable and Haskell modules (site.hs, ChaoDoc.hs,
SideNoteHTML.hs, Pangu.hs) to handle Pandoc/Hakyll compilation,
theorem/sidenote processing and CJK spacing. Add CSS, font files,
favicon, templates, Makefile, and a CSL bibliographic style. Update
.gitignore to ignore build artifacts.

math-macros.tex

@@ -0,0 +1,19 @@
+\newcommand{\floor}[1]{\left\lfloor #1 \right\rfloor}
+\newcommand{\ceil}[1]{\left\lceil #1 \right\rceil}
+\newcommand{\set}[1]{\left\{ #1 \right\}}
+\newcommand{\norm}[1]{\left\| #1 \right\|}
+\newcommand{\rm}[1]{\operatorname{#1}}
+
+\newcommand{\F}{\mathbb{F}}
+\newcommand{\R}{\mathbb{R}}
+\newcommand{\C}{\mathbb{C}}
+\newcommand{\Z}{\mathbb{Z}}
+\newcommand{\N}{\mathbb{N}}
+\newcommand{\e}{\varepsilon}
+
+\newcommand{\mex}{\operatorname{mex}}
+\newcommand{\lcm}{\operatorname{lcm}}
+\newcommand{\dist}{\operatorname{dist}}
+\newcommand{\poly}{\operatorname{poly}}
+\newcommand{\polylog}{\operatorname{polylog}}
+\newcommand{\span}{\operatorname{span}}