improve harvester wizard and documentation when dealing with author

Rather tricky to parameterise
I suspect a bug in the documentation find (a j cronin or v fitch). The correct syntax is find a j cronin or a v fitch.
The correct way is to alway specify the keyword a and to not use parenthesis.
In addition author names can be written j cronin or cronin, j.
For author with a double first name, there is only one way to write them nguyen, v g
For author with a first name starting with the letter a , we shall use find a albert einstein
A working example is the theory group from ipno. The following filter find their proceedings for 2016, but I don't know if all of them are found?:
```
  find a h sazdjian or a lansberg, j p or a s friot or a b moussallam or a v bernard or a j carbonell and date 2016 and tc c
```

To fix this issue: