Add Portuguese localisation for all markdown files

[justinyoo]

There are instructions written in English in the markdown format.

Translate all the markdown files into Portuguese and store them under the localisation/pt-br directory by keeping the directory structure. The list of markdown files are:

• /README.md
• /product-requirements.md
• all markdown files under the /complete directory and its subdirectory
• all markdown files under the /docs directory and its subdirectory
• /dotent/README.md
• /java/README.md
• /javascript/README.md
• /python/README.md

Here are some guidance:

1. Make sure that the link in the localised documents should not be broken.
2. Make sure that the image links are pointing to the original ones.
3. Make sure that all the sections in each doc are localised.
4. Make sure that all the prompts in each doc are localised.