Build failures in Nightly due to Proc macro API 1.2

[tirkarthi]

Project fails with Nightly compiler due to the recent proc macro API changes made that renames some of the components. It seems the release of proc macros 2 library with the changes already merged will fix the issue. I searched for issues here and couldn't find anything related to this. Hence I am opening this as a reminder. Feel free to close this if it's tracked elsewhere.

Upstream rustc issue reference : rust-lang/rust#50473 (comment)
Upstream proc macros 2 PR (merged) : dtolnay/proc-macro2#90

Thanks

[hcpl]

I made an update in #1021. Please check out my branch and see whether that fixes the problem!

[cramertj]

Fixed by #1021