I did Pkg.checkout("PyCall"); Pkg.build("PyCall") and PyCall is now version 1.1.2 master. The using Plots command still gives the error:
ERROR: ArgumentError: Docile not found in path in require at loading.jl:233 in stale_cachefile at loading.jl:439 in recompile_stale at loading.jl:457 in _require_from_serialized at loading.jl:83 in _require_from_serialized at loading.jl:109 in require at loading.jl:219