How to build a workflow for translating a site into English?

Question

Machine translation from one language to another

The task is to translate a large site by freelance translators.
Several points need to be taken into account:

• Translation of the content itself (articles/pages/product descriptions)
  
• Hardcode translation - part of the text is sewn directly into the site template
  
• Translation of meta-tags, alt-attributes of pictures and other trifles.
  
• All the rest...
  

Are there any services that provide a workflow where you can set translation tasks, track, and manage it all? There is no desire to get confused in tons of word-files.
PS Once upon a time I saw an article on Habré, which described how some company translated either a movie or a site where they managed everything in some system. I can't find it at all.