v0.8.65

ApproxFunBase v0.8.65

Diff since v0.8.64

Merged pull requests:

• Drop support for FillArrays <v1 (#629) (@jishnub)
• First/last for ConstantSpace Fun (#631) (@jishnub)
• Add isconstantfun and check while converting to ConstantSpace (#632) (@jishnub)
• Evaluate Fun{<:PointSpace} using a Point (#633) (@jishnub)
• Fix error message for unimplemented domain/rangespace (#634) (@jishnub)
• Use values in iszero (#635) (@jishnub)
• Backport isconstant (#637) (@jishnub)