Merge with UltiSnips repo (added fnct to merge)

- UltiSnips: Moved alias snippets from sh to all.

- Aliases: Snippet, commit message.
- Vim: Map fold method, preview and line break to leader keys.

UltiSnips/texmath.snippets

@@ -0,0 +1,23 @@
+snippet al "Align (math)" b
+\begin{align*}
+	$0
+\end{align*}
+endsnippet
+
+snippet pwf "Piecewise function" b
+\[
+	${1:name} = \left.
+	\begin{cases}
+		${2:equation}, & ${3:condition} \\\\
+	\end{cases}
+	\right\\}
+\]
+endsnippet
+
+snippet int "Integral" i
+\int_{${1:lower}}^{${2:upper}} \, \mathrm{d}${3:x}	
+endsnippet
+
+snippet ie "In-line equation" i
+$$1$$2
+endsnippet