v8.6.1

DataInterpolations v8.6.1

Diff since v8.6.0

Merged pull requests:

• Test allocations (#466) (@cgarling)
• Fix + test Integrating SmoothedConstantInterpolation without smoothing (#470) (@SouthEndMusic)
• Update to PrettyTables v3 (#471) (@jaakkor2)
• length check before return; also explicit error instead of @assert (#472) (@daviehh)
• Change header for show method from time to t. (#473) (@artkuo)
• bump version (#474) (@oscardssmith)