Fix time/date and deepObject binding issues

This fixes oapi-codegen#247. DeepObject had various bugs in binding to
time and dates, and we explicitly need to handle aliases
via reflection instead of type converting to time.Time and
types.Date

Added a pile of tests for these cases.

Fix errors imports.

We like "github.com/pkg/errors"

Replace gofmt by goimports and move the imports the template (oapi-co…

…degen#226)

Allow giving URLs to oapi-codegen (oapi-codegen#216)

* Detect non local paths

* Tests

Attempt to fix codegen issue of not including additionalProperties in…

… allOf schema (oapi-codegen#194)

Wrap Chi server and pass parameters as function params (oapi-codegen#166

)

* wrap server interface

* pass request and response to the handlers

* update examples and tests

* fix chi template

fixed broken enum generation (oapi-codegen#199)

* fixed broken enum generation

* removed unnecessary YAML parsing

feat: Add skipper using the echo convention to enable just that (oapi…

…-codegen#176)

feat: prune unused components by default (oapi-codegen#154)

* feat: prune unused components by default

* chore: rename commented code to use walkHeaderRef

* refactor: remove comment for issue in kin-openapi

* chore: add missing parameter name

Co-authored-by: John Stableford <john.stableford@digio.com.au>
Co-authored-by: John Stableford <john.stableford@latitudefinancial.com>

Fix parsing of empty date

This fixes oapi-codegen#140