Add lib to Makefile

[straight-shoota]

No description provided.

[RX14]

I'm less sure of this now, I think the behaviour should be this:

• the makefile should warn if lib doesn't exist
• the makefile should provide a bootstrap target
• the warning should contain instructions to either run shards or make bootstrap.

a good bootstrap for the makefile is:

MOLINILLO_VERSION = $(shell $(CRYSTAL) eval 'require "yaml"; puts YAML.parse(File.read("shard.lock"))["shards"]["molinillo"]["version"]')
MOLINILLO_URL = "https://github.com/crystal-lang/crystal-molinillo/archive/v$(MOLINILLO_VERSION).tar.gz"

with the target

bootstrap:
	mkdir -p lib/molinillo
	curl -L $(MOLINILLO_URL) | tar -xz -C lib/molinillo --strip-components=1

[straight-shoota]

@RX14 I've just enhanced the recipe for lib with bootstrap as a fallback if shards install fails. That way it should work without having to run a second command.
If you want to force the boostrap behaviour, you can run make lib SHARDS=false.

[RX14]

Why is this required? It really shouldn't be.

[straight-shoota]

See commit message on 4d559ac

tmp/integrations is created by integration specs and contains non-formatted files

[straight-shoota]

Maybe crystal/format-check (or crystal tool format) should only apply to spec src by default. But this is also a very specific problem that shards contains ill-formatted files in its tree after the test have run.

Alternatives would be to run format check before make test or clean tmp/integrations afterwards.

[RX14]

I think this is fine

[j8r]

Is it possible to move forward? Updating the Alpine Linux shards package requires bootstrapping to get molinillo.

[straight-shoota]

Rebased and squashed.