v0.17.4

FITSIO v0.17.4

Diff since v0.17.1

Merged pull requests:

• Add missing data type (UInt64/Culonglong) (#193) (@Heptazhou)
• Add repl language tags for examples (#195) (@abhro)
• Update CI setup (#197) (@giordano)
• Bump julia-actions/setup-julia from 1 to 2 (#198) (@dependabot[bot])
• add a more convenient FITSHeader constructor (#199) (@aplavin)
• add haskey(::FITS, key) (#200) (@aplavin)