Add support for cookie.txt files

[flocked]

It would be nice to add support for cookie text files that eg. can be exported using a browser extension.

[TUVIMEN]

Request options are derived from treerequests lib, it's developed to have arguments compatible with curl. You can export request from the browser as curl and copy headers e.g. -H 'header1=value1' -H 'header2=value2' -H 'Cookie: cookie1=value1; cookie2=value2'

Curl also supports cookies from files you can do -b cookie=value or -b cookie-file (netscape format is not supported yet)

There's also --browser option that copies cookies from current browser session e.g. --browser firefox