enable linter using golangci-lint across
codebase to run a bunch of linters together,
we shall enable new linters as we fix more
things the codebase.
This PR fixes the first stage of this
cleanup.
This commit modifies csv parser, a fork of golang csv
parser to support a custom quote escape character.
The quote escape character is used to escape the quote
character when a csv field contains a quote character
as part of data.
