Err: IOError: [Errno 2] No such file or directory: 'src/Ui/template/wrapper.html' in UiServer.py

### Step 1: Please describe your environment

* ZeroNet version: latest
* Operating system: Ubuntu 18.04 64bits
* Web browser: Firefox 60.0.2
* Tor status: always
* Opened port: yes
* Special configuration: no

### Step 2: Describe the problem:
After starting the command
I have the following error message in the browser
Server error
Err: IOError: [Errno 2] No such file or directory: 'src/Ui/template/wrapper.html' in UiServer.py line 95 > UiRequest.py line 130 > MutePlugin.py line 138 > UiRequest.py line 299 > UiRequest.py line 394 > UiRequest.py line **249**

#### Steps to reproduce:

1. Launch the command in the shell
> $ python2 zeronet.py

#### Observed Results:

"GATEWAY_INTERFACE": "CGI/1.1",
"HTTP_ACCEPT": "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8",
"HTTP_ACCEPT_ENCODING": "gzip, deflate",
"HTTP_ACCEPT_LANGUAGE": "en-GB,en;q=0.5",
"HTTP_CONNECTION": "keep-alive",
"HTTP_DNT": "1",
"HTTP_HOST": "127.0.0.1:43110",
"HTTP_UPGRADE_INSECURE_REQUESTS": "1",
"HTTP_USER_AGENT": "Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:60.0) Gecko/20100101 Firefox/60.0",
"PATH_INFO": "/1HeLLo4uzjaLetFx6NH3PMwFP3qbRbTf3D",
"QUERY_STRING": "",
"REMOTE_ADDR": "127.0.0.1",
"REMOTE_PORT": "39100",
"REQUEST_METHOD": "GET",
"SCRIPT_NAME": "",
"SERVER_NAME": "localhost",
"SERVER_PORT": "43110",
"SERVER_PROTOCOL": "HTTP/1.1",
"SERVER_SOFTWARE": "gevent/1.2 Python/2.7",
"arguments": {
"action": "main",
"autodownload_bigfile_size_limit": 1,
"batch": false,
"bind": null,
"bit_resolver": "1Name2NXVi1RDPDgf5617UoW7xA6YrhM9F",
"broadcast_port": 1544,
"coffeescript_compiler": null,
"config_file": "zeronet.conf",
"connected_limit": 8,
"data_dir": "data",
"db_mode": "speed",
"debug": false,
"debug_socket": false,
"disable_db": false,
"disable_encryption": false,
"disable_sslcompression": true,
"disable_udp": false,
"download_optional": "manual",
"end": true,
"file_size_limit": 10,
"fileserver_ip": "*",
"fileserver_port": 15441,
"fix_float_decimals": false,
"global_connected_limit": 512,
"homepage": "1HeLLo4uzjaLetFx6NH3PMwFP3qbRbTf3D",
"ip_external": null,
"ip_local": [
"127.0.0.1"
],
"keep_ssl_cert": false,
"language": "fr",
"log_dir": "log",
"log_level": "DEBUG",
"max_files_opened": 2048,
"msgpack_purepython": false,
"open_browser": "default_browser",
"optional_limit": "10%",
"pin_bigfile": 20,
"proxy": null,
"silent": false,
"size_limit": 10,
"stack_size": null,
"stream_downloads": false,
"tor": "always",
"tor_controller": "127.0.0.1:9051",
"tor_hs_limit": 10,
"tor_proxy": "127.0.0.1:9050",
"trackers": [
"zero://boot3rdez4rzn36x.onion:15441",
"zero://zero.booth.moe#f36ca555bee6ba216b14d10f38c16f7769ff064e0e37d887603548cc2e64191d:15441",
"udp://tracker.coppersurfer.tk:6969",
"udp://tracker.leechers-paradise.org:6969",
"udp://9.rarbg.com:2710",
"http://tracker.city9x.com:2710/announce",
"http://0d.kebhana.mx:443/announce",
"http://retracker.spark-rostov.ru:80/announce"
],
"trackers_file": false,
"ui_host": null,
"ui_ip": "127.0.0.1",
"ui_port": 43110,
"ui_restrict": false,
"updatesite": "1UPDatEDxnvHDo7TXvq6AEBARfNkyfxsp",
"use_openssl": true,
"use_tempfiles": false,
"verbose": false,
"workers": 5
},
"plugins": [
"AnnounceLocal",
"AnnounceZero",
"Bigfile",
"Chart",
"Cors",
"CryptMessage",
"FilePack",
"MergerSite",
"Mute",
"Newsfeed",
"OptionalManager",
"PeerDb",
"Sidebar",
"Stats",
"TranslateSite",
"Trayicon",
"Zeroname"
],
"version_gevent": "1.2.2",
"version_python": "2.7.15rc1 (default, Apr 15 2018, 21:51:34) \n[GCC 7.3.0]",
"version_zeronet": "0.6.2 r3323",
"wsgi.url_scheme": "http"
}
#### Expected Results:

* What did you expect to happen?
Should open the portal properly in the web browser

Empieza en la línea 95 de UiServer.py y sigue la ruta de llamadas indicada a través de UiRequest.py y MutePlugin.py. Reproduce el fallo con `python2 zeronet.py` y, después, inspecciona por qué la solicitud no puede encontrar `src/Ui/template/wrapper.html`; se considera terminado cuando el portal se abre correctamente sin el error de archivo faltante.

Escrito por el modelo de indexación a partir del texto del issue.