add skills seeds and implement api

ki/commands.py

@@ -0,0 +1,9 @@
+from ki.models import Skill
+from app import app, db
+
+
+@app.cli.command("seed")
+def seed():
+    db.session.add(Skill(id=1, name="PHP"))
+    db.session.add(Skill(id=2, name="Vue.js"))
+    db.session.commit()