v1.28.0

ExponentialUtilities v1.28.0

Diff since v1.27.0

Merged pull requests:

• Remove outdated Julia version checks (#188) (@ChrisRackauckas)
• Apply JuliaFormatter to fix code formatting (#189) (@ChrisRackauckas)
• Add spell checking configuration (#191) (@ChrisRackauckas)
• Apply JuliaFormatter to fix code formatting (#192) (@ChrisRackauckas)