Use product specific download pages instead of common one where possible

All product download links are currently available from the same page https://lifescience.opensource.epam.com/download/index.html

Users are referred to this page even in those cases when user has already selected needed product (e.g. https://lifescience.opensource.epam.com/imago/imago-gui.html). This leads to inconvenience as the user needs to search for needed product link again.

Please correct all product download references so that they open product specific download pages (e.g. https://lifescience.opensource.epam.com/download/bingo.html, https://lifescience.opensource.epam.com/download/ketcher.html) instead of the common one.