Add basic slider component

src/routes/components/FormField.md

@@ -1,9 +1,13 @@
 ```svelte example raised
 <script lang="ts">
     import { FormField } from "omorphia";
+    import { Slider } from "omorphia";
     import { TextInput } from "omorphia";
 </script>
 
+<FormField label="Favorite number">
+    <Slider min=0 max=100 value=69 />
+</FormField>
 <FormField label="Favorite color">
     <TextInput placeholder="Enter another color..." />
 </FormField>

src/routes/components/Slider.md

@@ -0,0 +1,7 @@
+```svelte example
+<script lang="ts">
+    import { Slider } from "omorphia";
+</script>
+
+<Slider min=0 max=10 value=4 />
+```