Arch Linux

Description:
Attempting to start Gitea will fail because assets are missing.

Steps to reproduce:
1. Start gitea with systemctl
2. Notice error in journalctl

Additional info:
- gitea 1.11.4-2
- this seems to be a build-time bug? attempting to manually place the locales into conf/locale/ will allow gitea to start, but then give 404/500 errors and in-browser will say `html/template: "home" is undefined`

```
Apr 04 18:46:08 sites.trwnh.com systemd[1]: Started Gitea (Git with a cup of tea).
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 cmd/web.go:107:runWeb() [I] Starting Gitea on PID: 635686
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 ...dules/setting/git.go:91:newGit() [I] Git Version: 2.26.0, Wire Protocol Version 2 Enabled
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 routers/init.go:87:GlobalInit() [T] AppPath: /usr/bin/gitea
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 routers/init.go:88:GlobalInit() [T] AppWorkPath: /var/lib/gitea
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 routers/init.go:89:GlobalInit() [T] Custom path: /var/lib/gitea/custom
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 routers/init.go:90:GlobalInit() [T] Log path: /var/log/gitea/
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: 2020/04/04 18:46:09 ...dules/setting/log.go:233:newLogService() [I] Gitea v1.11.4 built with GNU Make 4.3, go1.14.1 : sqlite, pam
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: panic: fail to set message file(en-US): open conf/locale/locale_en-US.ini: no such file or directory
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: goroutine 1 [running]:
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: gitea.com/macaron/i18n.initLocales(0xc0002e9615, 0x0, 0x55d974cb80b5, 0xb, 0xc0006b49f0, 0x55d974cc8a38, 0x12, 0xc00012cc00, 0x16, 0x20, ...)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: gitea.com/macaron/i18n@v0.0.0-20190822004228-474e714e2223/i18n.go:57 +0x68b
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: gitea.com/macaron/i18n.I18n(0xc0006df500, 0x1, 0x1, 0x0, 0x0)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: gitea.com/macaron/i18n@v0.0.0-20190822004228-474e714e2223/i18n.go:160 +0xef
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: code.gitea.io/gitea/routers/routes.NewMacaron(0x55d97544f080)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: code.gitea.io/gitea/routers/routes/routes.go:187 +0x937
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: code.gitea.io/gitea/cmd.runWeb(0xc0000c34a0, 0x0, 0x0)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: code.gitea.io/gitea/cmd/web.go:119 +0x2c8
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli.HandleAction(0x55d97515df00, 0x55d9753ebc30, 0xc0000c34a0, 0xc000077b00, 0x0)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli@v1.20.0/app.go:490 +0xca
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli.Command.Run(0x55d974ca6f2e, 0x3, 0x0, 0x0, 0x0, 0x0, 0x0, 0x55d974cd210d, 0x16, 0x0, ...)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli@v1.20.0/command.go:210 +0x9ea
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli.(*App).Run(0xc00011d860, 0xc00003c080, 0x4, 0x4, 0x0, 0x0)
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: github.com/urfave/cli@v1.20.0/app.go:255 +0x743
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: main.main()
Apr 04 18:46:09 sites.trwnh.com gitea[635686]: code.gitea.io/gitea/main.go:109 +0x818
Apr 04 18:46:09 sites.trwnh.com systemd[1]: gitea.service: Main process exited, code=exited, status=2/INVALIDARGUMENT
Apr 04 18:46:09 sites.trwnh.com systemd[1]: gitea.service: Failed with result 'exit-code'.
Apr 04 18:46:11 sites.trwnh.com systemd[1]: gitea.service: Scheduled restart job, restart counter is at 34011.
Apr 04 18:46:11 sites.trwnh.com systemd[1]: Stopped Gitea (Git with a cup of tea).
```