fisher: add page (#2387)

pages/common/fisher.md

@@ -0,0 +1,32 @@
+# fisher
+
+> Fisher, a fish-shell plugin manager.
+> Install plugins by name or from a managed 'fishfile' for bundled installs.
+
+- Install one or more plugins:
+
+`fisher {{plugin1}} {{plugin2}}`
+
+- Install a plugin from a GitHub gist:
+
+`fisher {{gist_url}}`
+
+- Edit 'fishfile' by hand with your favorite editor and install multiple plugins:
+
+`{{editor}} ~/.config/fish/fishfile; fisher`
+
+- List installed plugins:
+
+`fisher ls`
+
+- Show available plugins:
+
+`fisher ls-remote`
+
+- Update plugins:
+
+`fisher up`
+
+- Remove one or more plugins:
+
+`fisher rm {{plugin1}} {{plugin2}}`