proxy_force can break download b/c of bug in libtorrent so make it configurable

[antonsoroko]

Description

there is a some bug that prevents download of data and metadata (magnets cannot be not resolved) if proxy_force=true, checked with socks5 and http with local proxy from tinyproxy and proxy from windscribe app. download always "hangs" with proxy_force.
looks like there is some bug in libtorrent 1.1 (that we use) regarding proxy_force option.

Related Issue

originally added here elgatito/elementum#84

this PR depends on elgatito/elementum#149

Motivation and Context

How Has This Been Tested?

test build.
tested with socks5 and http types with local proxy from tinyproxy and proxy from windscribe app.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Translation

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.