Allow base 4.15 for GHC 8.10

[TravisWhitaker]

This depends on:

• Allow GHC 8.10 + 9.0 and bytestring 0.11 svg-builder#12
• master of monoid-extras
• Allow base 4.15 for GHC 8.10 active#31
• allow base-4.14 for GHC-8.10 diagrams-lib#349
• Allow base 4.15.x for GHC 8.10 dual-tree#13
• Allow base 4.15 for GHC 8.10 diagrams-core#113

For anyone else who needs to use this package (and all of its deps) with GHC 8.10, here's a cabal.project that works:

packages: .

source-repository-package
    type: git
    location: https://github.com/sjakobi/svg-builder
    tag: ff3a4b0fdfcdf8cfa0d08564733024b63121bd65

source-repository-package
    type: git
    location: https://github.com/diagrams/monoid-extras
    tag: 216a82109c38bf0c692b32db11a424bcb0b54f8e

source-repository-package
    type: git
    location: https://github.com/TravisWhitaker/active
    tag:8e5f8d7ebf12970dbe65c5df36e44c12f9b221ab

source-repository-package
    type: git
    location: https://github.com/thielema/diagrams-lib
    tag: 2d06dfca86292b454cc0041aef6e68b646237f3d

source-repository-package
    type: git
    location: https://github.com/TravisWhitaker/dual-tree
    tag: bd8e5b75f7e117420ade237e62a025a511361061

source-repository-package
    type: git
    location: https://github.com/TravisWhitaker/diagrams-core
    tag: a9456cf1c6cd3aff2c4dbf095df6dec6e51fa21c

[sjakobi]

Ping @byorgey! :)

[byorgey]

@sjakobi @TravisWhitaker My apologies. Of course this has been a really crazy year. I would really like to be able to update all the diagrams packages, and I do intend to, but realistically, I will not have time to do so until June. I'm very glad that others have been finding workarounds to continue using diagrams for now. If anyone else would like to help with merging updates like this and making some releases to Hackage I would welcome the help.

[sjakobi]

@byorgey Thanks for the offer, but I kind of don't want to be the guy who keeps the lights on in yet another project that I'm not passionate about. I've already collected a few of those.

I'm also worried about crowding out other potential co-maintainers who have a deeper interest in this project.

However, if you could find a co-maintainer who does have a deeper interest in this project, I'd be willing to assist with things like CI and compatibility issues.

Regarding finding a co-maintainer: Are you aware of any regular contributors who might be interested? You could also consider sending out a request on the mailing lists, Discourse and/or r/haskell. Some of Chris Done's projects got new maintainers in this way.

[byorgey]

@sjakobi Sure, I wasn't necessarily suggesting that you in particular might want to help, the comment was more intended for anyone else who might happen along and read this issue. Good suggestions re: looking for co-maintainers.

[byorgey]

diagrams-svg has been revised on Hackage and now builds up through GHC 9.0.