T12: Fetch Categories - Githubissues

[x] Fetch categories by thunk action and store it in the gobal reducer
[x] endpoint /categories
[x] list categories on the screen
[x] categories should be link
[x] on click it should navigate to /shop/:gender/:category
samples: shop/kadin/ayakkabi shop/erkek/gomlek
[x] top 5 categories should be listed on the screen with images regarding rating value
[x] all categories should be listed in drop down menu on header
[x] Drop down menu should be in the same format as below:

evren-aydin / ecommerce