Update badges in README and fix typos (#87)

Fix racy code in batch publisher

Merge pull request #77 from CanLikeTo/add_span_ctx

Add span_ctx to EventMetadata

Merge pull request #75 from stoewer/issue-74-golangci-lint-fails

Install golangci-lint from tar file

Merge pull request #63 from VahanN95/master

Support subscrption authorization

Merge pull request #60 from stoewer/issue-59

 Reopen a new stream when the processor fails to commit a cursor

Merge pull request #57 from stoewer/issue-55

Support Go 1.11 modules

Merge pull request #53 from krnkl/issue-52

LGTM

Merge pull request #51 from krnkl/issue-50

LGTM

Merge pull request #47 from krnkl/issue-46

fixed calls of NotifyErr callback in the Processor