Fix: Move Python and NodeJS pages

[arunkarthik-periyaswamy]

• Moved the Python and NodeJS pages from Howtos to Developer's sections.
• Updated the navigation menu in Developers section

[arunkarthik-periyaswamy]

Hello @nlsdvl can you please review this Addresses: #12

[nlsdvl]

Hello @arunkarthik-periyaswamy , thanks a lot for helping out on this one.

Can add the http redirections configuration to support the changes, eg. so that '/Howtos/python/' redirects to '/Developers/python/' ? I was looking at mkdocs-redirects to handle this.

I tried your changes localy, for python this works well.

For javascript, your changes creates a 'NodeJS' menu item alongside the 'javascript' one, I'm not sure about that.
The intent with the 'javascript' page is to provide an entry point to js developers that exposes the 2 options to work with GPAC 'NodeJS bindings' vs 'JSFilters plugins'.

I think we can just remove the Javascript page, and instead better emphasize the difference between NodeJS and JSFilters at the top of NodeJS page directly. The alternative would be to add NodeJS as a subsection of the Javascript menu somehow, that would make sense if this section is expected to grow over time. cc @jeanlf

[rbouqueau]

@arunkarthik-periyaswamy No news on this?