[emacs] Add snippets for latex mode.

.emacs.d/snippets/latex-mode/block.yasnippet

@@ -0,0 +1,9 @@
+# -*- mode: snippet -*-
+# contributor: Claudio Marforio <marforio@gmail.com> 
+# key: block
+# group: environments
+# name : \begin{*block} ... \end{*block}
+# --
+\begin{${1:$$(yas/choose-value '("block" "exampleblock" "alertblock"))}}{${2:Block Title}}
+
+\end{$1}