Restore buttons referenced in current templates

Partial revert of 271d9e05 - these are two of the many files removed then. Looks like these are the only two still used.

pinaxcon/templates/cms_pages/home_page_blocks/btn_generic_link.html

@@ -0,0 +1,24 @@
+<svg id="Layer_1" data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 57 57">
+  <defs>
+      <style>
+          .web-cls-1 {
+              fill: none;
+          }
+
+          .web-cls-2 {
+              clip-path: url(#clip-path);
+          }
+
+          .web-cls-3 {
+              fill: currentColor;
+          }
+      </style>
+      <clipPath id="clip-path">
+          <rect class="web-cls-1" width="57" height="57"></rect>
+      </clipPath>
+  </defs>
+  <title>website</title>
+  <g class="web-cls-2">
+      <path class="web-cls-3" d="M33.78,43.33A9.74,9.74,0,0,1,27,40.49l-2.84-2.84a1.1,1.1,0,0,1,0-1.59l1.59-1.59a1.09,1.09,0,0,1,1.59,0l2.84,2.84a5,5,0,1,0,7-7l-2.84-2.84a1.1,1.1,0,0,1,0-1.59l1.59-1.59a1.1,1.1,0,0,1,1.59,0l2.84,2.84a9.56,9.56,0,0,1,2.84,6.82,9.41,9.41,0,0,1-9.44,9.44M23.21,24.81l1.59-1.59a1.09,1.09,0,0,1,1.59,0l7.5,7.5a1.09,1.09,0,0,1,0,1.59L32.3,33.9a1.09,1.09,0,0,1-1.59,0l-7.5-7.5a1.09,1.09,0,0,1,0-1.59m-0.57,6.48-1.59,1.59a1.1,1.1,0,0,1-1.59,0L16.62,30a9.56,9.56,0,0,1,6.71-16.37,9.72,9.72,0,0,1,6.82,2.84L33,19.35a1.09,1.09,0,0,1,0,1.59L31.4,22.53a1.1,1.1,0,0,1-1.6,0L27,19.69a5,5,0,0,0-3.52-1.48,5,5,0,0,0-5,5,5,5,0,0,0,1.48,3.52l2.84,2.84a1.81,1.81,0,0,1-.11,1.7M28.5,0A28.5,28.5,0,1,0,57,28.5,28.5,28.5,0,0,0,28.5,0"></path>
+  </g>
+</svg>

pinaxcon/templates/cms_pages/home_page_blocks/btn_twitter.html

@@ -0,0 +1,24 @@
+<svg id="Layer_1" data-name="Layer 1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 57 57">
+    <defs>
+        <style>
+            .twtr-cls-1 {
+                fill: none;
+            }
+
+            .twtr-cls-2 {
+                clip-path: url(#clip-path);
+            }
+
+            .twtr-cls-3 {
+                fill: currentColor;
+            }
+        </style>
+        <clipPath id="clip-path" transform="translate(0 0)">
+            <rect class="twtr-cls-1" width="57" height="57"></rect>
+        </clipPath>
+    </defs>
+    <title>twitter</title>
+    <g class="twtr-cls-2">
+        <path class="twtr-cls-3" d="M39.83,22.69c0,0.25,0,.5,0,0.75,0,7.73-5.88,16.64-16.64,16.64a16.55,16.55,0,0,1-9-2.63,12.38,12.38,0,0,0,1.4.08A11.72,11.72,0,0,0,22.91,35,5.86,5.86,0,0,1,17.45,31a6,6,0,0,0,1.1.1,5.89,5.89,0,0,0,1.54-.2,5.86,5.86,0,0,1-4.69-5.73V25.07A5.82,5.82,0,0,0,18,25.8,5.85,5.85,0,0,1,16.23,18,16.59,16.59,0,0,0,28.29,24.1a5.85,5.85,0,0,1,10-5.33A11.66,11.66,0,0,0,42,17.35a5.87,5.87,0,0,1-2.57,3.24,11.65,11.65,0,0,0,3.36-.92,11.84,11.84,0,0,1-2.92,3M28.5,0A28.5,28.5,0,1,0,57,28.5,28.5,28.5,0,0,0,28.5,0" transform="translate(0 0)"></path>
+    </g>
+</svg>