Add -state-key CLI argument to lhtogitlab

Add -state-key new CLI argument to lhtogitlab to allow customizing the
GitLab scoped label key used to map Lighthouse ticket states to GitLab
labels.

Remove unneeded functionality from lhtogitlab

Don't bother reading bins, changesets or messages from LH export
archive since we don't do anything with them.  Also, don't read all
ticket attachments into memory at start of migration since this
consumes far too much memory.

cmd/lhtogitlab/README.md

@@ -25,6 +25,8 @@ Usage of lhtogitlab:
  GitLab base URL to use (i.e., https://gitlab.example.com/)
  -delete
  Delete all GitLab projects and users (except user owning API token -token) before importing
+ -groups string
+ Path to JSON file containing GitLab groups to create
  -insecure
  Allow insecure HTTPS connections to GitLab API
  -milestone string
@@ -42,14 +44,15 @@ Usage of lhtogitlab:
 ```
 
 Required arguments are `-base-url`, `-token` and `-users`. See the
-next section for the expected format of the file specified by
-`-users`. The final argument to `lhtogitlab` must be the path to a
-Lighthouse export file generated by the `lh export` command.
+next two sections for the expected format of the file specified by
+`-users` and `-groups`. The final argument to `lhtogitlab` must be
+the path to a Lighthouse export file generated by the `lh export`
+command.
 
 See [cmd/lh](https:/nwidger/lighthouse/blob/master/cmd/lh)
 for more details about the usage of the `lh export` command.
 
-## Users Map
+## Users File
 
 The `-users` argument specifies a path to a JSON file mapping
 Lighthouse user ID's to GitLab users. Each user will be created in
@@ -59,23 +62,88 @@ for an example:
 ``` json
 {
  "123": {
- "name": "Bob Bobbington",
+ "email": "[email protected]",
  "username": "bob",
- "email": "[email protected]"
+ "projects_limit": 100000,
+ "name": "Bob Bobbington",
+ "is_admin": true,
+ "external": false,
+ "can_create_groups": true
  },
  "456": {
- "name": "Fred Freddington",
+ "email": "[email protected]",
  "username": "fred",
- "email": "[email protected]"
+ "projects_limit": 100000,
+ "name": "Fred Freddington",
+ "is_admin": true,
+ "external": false,
+ "can_create_groups": true
  },
  "789": {
- "name": "Bill Billington",
+ "email": "[email protected]",
  "username": "bill",
- "email": "[email protected]"
+ "projects_limit": 100000,
+ "name": "Bill Billington",
+ "is_admin": true,
+ "external": false,
+ "can_create_groups": true
  }
 }
 ```
 
+## Groups File
+
+The `-groups` argument specifies a path to a JSON file containing an
+array of GitLab groups to create. Each group will be created in
+GitLab using the name, path and description fields provided.
+Lighthouse projects with a matching name in the `projects` array will
+be created within the given GitLab group. Lighthouse users with a
+matching name in the `members` array will be added as members within
+the given GitLab group. See below for an example:
+
+``` json
+[
+ {
+ "name": "Foo Bar",
+ "path": "foo-bar",
+ "description": "Foo bar",
+ "projects": [
+ "Foo Bar Project",
+ "Foo Bar Project 2"
+ ],
+ "members": [
+ "Bob Bobbington",
+ "Fred Freddington"
+ ]
+ },
+ {
+ "name": "Foo Buz",
+ "path": "foo-buz",
+ "description": "Foo buz",
+ "projects": [
+ "Foo Buz Project"
+ ],
+ "members": [
+ "Fred Freddington"
+ ]
+ },
+ {
+ "name": "Foo Buq",
+ "path": "foo-buq",
+ "description": "Foo buq",
+ "projects": [
+ "Foo Buq Project"
+ "Foo Buq Project 2"
+ "Foo Buq Project 3"
+ ],
+ "members": [
+ "Fred Freddington",
+ "Bill Billington"
+ ]
+ }
+]
+```
+
 ## Output
 
 The tool prints a line to standard out for each user, project,