Updated timelines

Slavery Timeline - Memphis Beatty
Cinco De Mayo: La Batalla de Puebla
Khmer/Angkor Empire
ch 13
Internet Timeline
Calendario de implementación
The United States in World Affairs
Esencia Verde
1960s Events
Desenvolvimento Embrionário
United States in the Inter-War
historia delas tic
Events Contributing to Canadian Identity
Evolución de la Calidad
Contexto de surgimento da sociologia
Second world war