v0.13.4

AbstractPPL v0.13.4

Diff since v0.13.3

Added missing methods for subsumes(::IndexLens, ::PropertyLens) and vice versa.

Merged pull requests:

• shift interface in README to docs (#144) (@penelopeysm)
• Fix missing subsumes methods for different lens types (#145) (@penelopeysm)

Closed issues:

• subsumes is missing a method (#129)