mannualy specify url for boost

[zt-chen]

The sunset of bintray invalidated the url of boost source (boostorg/boost#502), and the https://github.com/ruslo/hunter repo is not being maintained anymore.

So one solution is to manually specify the new URL of the boost source archive, or

ethminer/CMakeLists.txt

Line 17 in ce52c74

URL "https://github.com/ruslo/hunter/archive/v0.23.112.tar.gz"

need to be updated to use an actively maintained hunter.

This is a small patch aim to fix #2282

[zt-chen]

This should be able to fix #2290 too

[xaliander]

Approved change:
The error described below is solved by this commit. However, the URL could also be updated to the newest boost version. Please review @aloisklink.

Root of the problem:
Boost has moved downloads to JFrog Artifactory [1].

Error message:

-- File already exists but hash mismatch. Removing...
-- Downloading...
   dst='/home/user/.hunter/_Base/Download/Boost/1.66.0/075d0b4/boost_1_66_0.7z'
   timeout='none'
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
-- Retrying...
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
-- Retry after 5 seconds (attempt #2) ...
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
-- Retry after 5 seconds (attempt #3) ...
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
-- Retry after 15 seconds (attempt #4) ...
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
-- Retry after 60 seconds (attempt #5) ...
-- Using src='https://dl.bintray.com/boostorg/release/1.66.0/source/boost_1_66_0.7z'
CMake Error at Build/Boost-prefix/src/Boost-stamp/download-Boost.cmake:159 (message):
  Each download failed!

[aloisklink]

It looks good to me, but it would be slightly better to instead update hunter.

@arrichter, I'm not a maintainer of this repo, so I unfortunately can't merge this 😢
I don't think there's anyone with admin access actively maintaining this repo, so it's unlikely for this to get merged.
It might be worth contacting one of the people in https://github.com/ethereum-mining/ethminer#maintainers--authors if you want this to be merged (and maybe give them a tip if you do, since they're not getting paid for open-source).

@ChazyTheBest, you should be able to use the system boost library by setting HUNTER_ENABLED=NO, e.g. by doing cmake .. -DHUNTER_ENABLED=NO

[aloisklink]

A better way of doing this would be to upgrading hunter to the latest version, by changing lines

ethminer/CMakeLists.txt

Lines 16 to 20 in ce52c74

	HunterGate(
	URL "https://github.com/ruslo/hunter/archive/v0.23.112.tar.gz"
	SHA1 "4b894e1d5d203f0cc9a77431dbb1b486ab6f4430"
	LOCAL
	)

to:

HunterGate(
    URL "https://github.com/cpp-pm/hunter/archive/v0.23.320.tar.gz"
    SHA1 "9b4e732afd22f40482c11ad6342f7d336634226f"
    LOCAL
)

and specifying a version for jsoncpp (the latest version by hunter changes linking).

Suggested change

	hunter_config(
	Boost
	VERSION 1.66.0_new_url
	SHA1 f0b20d2d9f64041e8e7450600de0267244649766
	URL https://boostorg.jfrog.io/artifactory/main/release/1.66.0/source/boost_1_66_0.tar.gz
	)
	hunter_config(Boost VERSION 1.66.0)
	hunter_config(jsoncpp VERSION 1.8.0)

But this also works!