Add onionshare CLI to cli folder, move GUI to desktop folder, and start refactoring it to work with briefcase

docs/source/_static/custom.css

@@ -1,21 +0,0 @@
-.wy-nav-top {
-    background-color: #4e0d4e;
-}
-
-.wy-side-nav-search {
-    background-color: #5f0f5f;
-}
-
-.wy-nav-content a:link,
-.wy-nav-content a:visited {
-    color: #2980b9;
-}
-
-.wy-nav-content a:active,
-.wy-nav-content a:hover {
-    color: #3091d1;
-}
-
-.wy-nav-content div[role=navigation] {
-    display: none;
-}