Added Ultisnips snippets

.config/nvim/UltiSnips/lean3.snippets

@@ -0,0 +1,23 @@
+snippet \and "and" A
+∧
+endsnippet
+
+snippet \or "and" A
+∨
+endsnippet
+
+snippet \neg "not" A
+¬
+endsnippet
+
+snippet \to "\to ->" A
+→
+endsnippet
+
+snippet \iff "\iff <->" A
+↔
+endsnippet
+
+snippet \forall "forrall" A
+∀
+endsnippet

.config/nvim/UltiSnips/tex.snippets

@@ -0,0 +1,14 @@
+snippet fig "figure" 
+\begin{figure}
+	\centering
+	\includegraphics[width=.8\textwidth]{$1}
+	\caption{$3}
+	\label{$2}
+\end{figure}
+endsnippet
+
+snippet \beg "\begin{}...\end{}"
+\begin{$1}
+	$0
+\end{$1}
+endsnippet