Feature/LEWW-69 | Landing updated (Multi-language) + night-day color mode switch + section updates (faqs, contact, testimonials)

What?

@exequielrafaela - LEWW-69 | adding new images for landing and testimonials - 9c803c8
@exequielrafaela - LEWW-69 | upgrading material mkdocs image version + adding support to multi-language, night-day color mode + passing GAnalytics Key as env var - 70b20b3
@exequielrafaela - BBL-192 | Adding landing in spanish + placeholder new spanish sections - a129645
@exequielrafaela - LEWW-69 | updating contact info + faqs why leverage? + new testimonials + landing updated - 0f12faa