Error inspection

closed issues

Was planning to add error categorization, but end up implemented error inspection in go 2 proposal.
Also got a silly banner from @at15 \w/

New feature

• #66 error inspection without checking string, based on go 2 proposal
• #105 gommon add-build-ignore used for disable all the legacy packages

Partial

• #74 created go.mod so gommon be used by the replace directive in other
  go mod based projects, gommon itself is still using dep
• #103 style guide, only covered general and is not well formatted

Removed package

• #68 deprecate request package, use httpclient in go.ice#37