Expanded linting + fix warnings (#1396)

* Expand the linters and types of warnings to improve consistency and safety

* Fail lint workflow if there are errors

* golint has been replaced by revive

* Hand-pick some of the default exclude list

* Ignore error when trying to delete preview gif

* Ignore linter warning opening playlist path

* Rename user field Id -> ID

* A bunch of renames to address linter warnings

* Rename ChatClient -> Client per linter suggestion best practice

* Rename ChatServer -> Server per linter suggestion best practice

* More linter warning fixes

* Add missing comments to all exported functions and properties

.golangci.yml

@@ -1,14 +1,28 @@
 run:
   tests: false
+  modules-download-mode: readonly
 
 issues:
+  # The linter has a default list of ignorable errors. Turning this on will enable that list.
+  exclude-use-default: false
+  
+  # Maximum issues count per one linter. Set to 0 to disable. Default is 50.
   max-issues-per-linter: 0
+  
+  # Maximum count of issues with the same text. Set to 0 to disable. Default is 3.
   max-same-issues: 0
 
+  exclude:
+    - Subprocess launch(ed with variable|ing should be audited)
+    - Error return value of .((os\.)?std(out|err)\..*|.*Close|.*Flush|os\.Remove(All)?|.*print(f|ln)?|os\.(Un)?Setenv). is not checked
+    - G307 # Allow closing files as a defer without checking error.
+    - composite literal uses unkeyed fields
+
 linters:
   enable:
     - bodyclose
     - dupl
+    - errcheck
     - exportloopref
     - goconst
     - godot
@@ -16,10 +30,13 @@ linters:
     - goimports
     - goprintffuncname
     - gosec
+    - govet
     - misspell
     - prealloc
+    - revive
     - rowserrcheck
     - sqlclosecheck
+    - staticcheck
     - unconvert
     - unparam
     - whitespace
@@ -27,4 +44,4 @@ linters:
 linters-settings:
   govet:
     disable:
-      - composites
+      - composite