v0.2.0

BlockTensorKit v0.2.0

Diff since v0.1.13

This version contains a minor update to the SumSpace struct, such that it can now retain the isdual information even when working with empty spaces. This resolves many edge-case bugs and issues, but does constitute a breaking change.

Merged pull requests:

• Add dual flag to SumSpace (#32) (@lkdvos)