Update to crystal 0.26

[bcardiff]

Note: This changes should be backward compatible with 0.25.1
Ref: crystal-lang/crystal#6414

ivar initializers will be evaluated without self in context.

Disclaimer: I've only checked that the source build with crystal nightly together with this patch.

[Sija]

Why not use *args and super?

[bcardiff]

It was the minimum change. But it should be equivalent.

[Sija]

Also, there's one more:

Error in src/pet-tracker.cr:3: instantiating 'Amber::Server.class#start()'

Amber::Server.start
              ^~~~~

in lib/amber/src/amber/server/server.cr:17: instantiating 'Amber::Server#run()'

      instance.run
               ^~~

in lib/amber/src/amber/server/server.cr:50: instantiating 'start()'

        start
        ^~~~~

in lib/amber/src/amber/server/server.cr:59: undefined method 'tls=' for HTTP::Server

      server.tls = Amber::SSL.new(settings.ssl_key_file.not_nil!, settings.ssl_cert_file.not_nil!).generate_tls if ssl_enabled?
             ^~~

[bcardiff]

I didn't detect that because building the specs does not stress that path 🤔 .

To fix that, either something like kemalcr/kemal#477 can be done, or
since crystal-lang/crystal#6500 is merged, a more opaque bind can be used.

[bcardiff]

I also noticed that the shell-table shard version will need to be updated to support 0.26.0 jwaldrip/shell-table.cr#2

[robacarp]

@bcardiff thanks for this, I've picked your commit over to #929 and will finish the effort there.