syntax that fits English grammar

Instead of

```
equiv sinatra of python
```

it would make more sense to English speakers to write

```
equiv of sinatra in python
```

(It also would be okay to do

```
equiv sinatra python
```

if you prefer to keep it sparse, but once you put `of` in there, it's very confusing if it's breaking English grammatical patterns. The downside of this approach is that it requires you to remember argument order, and might get pretty confusing if later you add new features which depend on new additional arguments.

Yet another option would be

```
equiv --of sinatra --in python
```