shards: add page (#2372)

pages/common/shards.md

@@ -0,0 +1,23 @@
+# shards
+
+> Dependency management tool for the Crystal language.
+
+- Create a skeleton shard.yml file:
+
+`shards init`
+
+- Install dependencies from a shard.yml file:
+
+`shards install`
+
+- Update all dependencies:
+
+`shards update`
+
+- List all installed dependencies:
+
+`shards list`
+
+- List version of dependency:
+
+`shards version {{path/to/dependency_folder}}`