Open-source development monetization

[PatchRanger]

In short: this PR proposes a way to monetize open-source development of your project. The idea is similar to how free-to-play works in gamedev industry: "You are free to wait for the package download - but in case if time is money for you, please consider buying non-waiting access to the package, every cent goes to the package developer to incentive the open-source development."

For details please refer to https://github.com/Free2Wait/composer-free2wait .

According to packagist statistics of your package https://packagist.org/packages/servo/fluidxml/stats , in theory it could bring to you about 2,931 (installs per month) * 0.03 (estimated conversion installs-to-sale) * 5 (price of each non-waiting access per month) = estimated $439.65 per month.

Please give me your feedback about the idea: what do you think? Are you interested in monetizing open-source development? Do you have any suggestions? Concerns?

Would be glad to receive any feeedback. Thank you for attention.