Add proxyCookies option

[SebastiaanYN]

This PR adds a proxyCookies option which resolves #333.

An issue with this PR is that it includes the cookie package and other code both on the server and client, while it only has to run on the server. It would be better to only include it on the server, but I'm unsure how that can be done.

I also haven't added any tests, because I'm not sure how this can be properly tested.

[codecov[bot]]

Codecov Report

Merging #358 into dev will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##               dev      #358   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            1         1           
  Lines           31        31           
  Branches        13        13           
=========================================
  Hits            31        31           

Impacted Files	Coverage Δ
lib/module.js	100.00% <ø> (ø)

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[k0mar12]

@pi0 Still get problems with ssr cookie. Any idea about merge this pull request?

[arkhamvm]

@pi0 can you clarify please, Nuxt 3 have same behavior, or this cookie-proxy is obsolete?