v0.7.34

ApproxFunBase v0.7.34

Diff since v0.7.33

Merged pull requests:

• Use SVector instead of Vec (#264) (@jishnub)
• Support SVector in PiecewiseSegment (#265) (@jishnub)
• Relax signature in promoteplus (#266) (@jishnub)
• Namespace in Calculus operator macro (#267) (@jishnub)