Deprecation warnings when building dproto test with DMD v2.073.0

[Arun]

I'm not sure if this is a bug in dproto or painlesstraits.

18:10:42 ~/.dub/packages/dproto-2.1.0/dproto
$ dub test
Generating test runner configuration 'dproto-test-library' for 'library' (library).
Performing "unittest" build using dmd for x86_64.
painlesstraits 0.0.3: building configuration "library"...
dproto 2.1.0: building configuration "dproto-test-library"...
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
import/dproto/attributes.d(71,20): Deprecation: std.traits.Identity(alias A) is not visible from module unittests
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
../../painlesstraits-0.0.3/painlesstraits/source/painlesstraits.d(45,31): Deprecation: std.traits.Identity(alias A) is not visible from module painlesstraits
import/dproto/attributes.d(71,20): Deprecation: std.traits.Identity(alias A) is not visible from module unittests
...

[Matt Soucy]

Should be fixed by updating to use v2.1.1