Bootstrap 4 update

[kimdv]

Well, this is the first approach to something.

Still, need some work and refinements!

• [x] Update about page
• [x] Update main page
• [x] Update accessories page
• [x] Update accessory detail page
• [x] Update contribute page
• [x] Update manufactures page
• [x] Update manufacture detail page
• [x] Update apps page
• [x] Update app detail page
• [x] Update contact page

[kimdv]

@BalestraPatrick I think I have something we can start review 🚀