add golangci config file, make sure http resp body is closed

.golangci.yml

@@ -0,0 +1,106 @@
+# options for analysis running
+run:
+  # default concurrency
+  concurrency: 2
+  # timeout
+  deadline: 20s
+  # include test file
+  tests: false
+  # which dirs to skip
+  skip-dirs:
+    - example
+  # which files to skip
+  skip-files:
+  # exit code when at least one issue was found
+  issues-exit-code: 1
+
+
+# output configuration options
+output:
+  format: colored-line-number
+  print-issued-lines: true
+  print-linter-name: true
+
+# all available settings of specific linters
+linters-settings:
+  errcheck:
+    check-type-assertions: true
+    check-blank: true
+  govet:
+    check-shadowing: true
+  gofmt:
+    simplify: true
+  goconst:
+    min-len: 3
+    min-occurrences: 3
+  misspell:
+    locale: UK
+  unused:
+    check-exported: false
+  unparam:
+    algo: cha
+  nakedret:
+    max-func-lines: 30
+  prealloc:
+    simple: true
+    range-loops: true
+    for-loops: true
+
+linters:
+  enable:
+    - deadcode
+    - govet
+    - ineffassign
+    - staticcheck
+    - structcheck
+    - typecheck
+    - unused
+    - varcheck
+    - bodyclose
+    - depguard
+    - dupl
+    - goconst
+    - gofmt
+    - goimports
+    - gosec
+    - misspell
+    - nakedret
+    - prealloc
+    - unconvert
+
+issues:
+  exclude-use-default: false
+  exclude:
+    # errcheck: Almost all programs ignore errors on these functions and in most cases it's ok
+    - Error return value of
+      .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*printf?|os\.(Un)?Setenv).
+      is not checked
+
+    # golint: Exported variables are rarely used and generally reserved for errors which should be self explanitory
+    - exported var \w+ should have comment or be unexported
+
+    # golint: False positive when tests are defined in package 'test'
+    - func name will be used as test\.Test.* by other packages, and that
+      stutters; consider calling this
+
+    # gas: Too many false-positives on 'unsafe' usage
+    - Use of unsafe calls should be audited
+
+    # gas: Too many false-positives for parametrized shell calls
+    - Subprocess launch(ed with variable|ing should be audited)
+
+    # gas: Duplicated errcheck checks
+    - G104
+
+    # gas: Too many issues in popular repos
+    - (Expect directory permissions to be 0750 or less|Expect file permissions
+      to be 0600 or less)
+
+    # gas: False positive is triggered by 'src, err := ioutil.ReadFile(filename)'
+    - Potential file inclusion via variable
+
+    # govet: Common false positives
+    - (possible misuse of unsafe.Pointer|should have signature)
+
+    # megacheck: Developers tend to write in C-style with an explicit 'break' in a 'switch', so it's ok to ignore
+    - ineffective break statement. Did you mean to break out of the outer loop