Failed to execute script boot: No module named gevent

### Step 1: Please describe your environment

* ZeroNet version: Latest (0.6.2)
* Operating system: Windows 10
* Python Version: 2.7.15

### Step 2: Describe the problem:
When I try and launch ZeroNet.exe I get the error "Failed to execute script boot". So, I decided to try and execute zeronet.py from within the core directory and this gave a bit more detail:
```
ERROR:root:Unhandled exception: No module named gevent
Traceback (most recent call last):
File "zeronet.py", line 18, in main
import main
File "C:\Users\Eddie\Documents\ZeroNet\ZeroNet-win-dist\core\src\main.py", line 9, in
import gevent
ImportError: No module named gevent
- Starting ZeroNet...
Traceback (most recent call last):
File "zeronet.py", line 91, in
main()
File "zeronet.py", line 64, in main
traceback.print_exc(file=open(config.log_dir + "/error.log", "a"))
AttributeError: 'Config' object has no attribute 'log_dir'
```
Thing is, I have already installed gevent with pip even with the --user arguments as I saw suggested on another issue...

I've also tried `python -m pip install gevent msgpack-python` too

It literally worked on the same machine about 1 week ago but I since removed the directory by accident and was going to try again...

Any ideas @HelloZeroNet?

Start with zeronet.py and core/src/main.py, using the reported Windows 10 launch failure and missing gevent traceback to reproduce the problem. Check how ZeroNet.exe obtains its Python dependencies and handles the error path; done means the executable starts without the missing-module or log_dir errors.

索引モデルが issue の本文から書いたものです。