add Landing page (#7)

src/components/landing/index.ts

@@ -0,0 +1,7 @@
+export * from './CtaButton';
+export * from './PageSection';
+export * from './BenefitsSection'; // CtaButton, PageSection
+export * from './SocialProofSection'; // CtaButton, PageSection
+export * from './SiteLogo';
+export * from './Footer'; // PageSection, SiteLogo
+export * from './HeroSection'; // CtaButton, PageSection, SiteLogo