global halts the repl

Trying to list all `globals` yields in unresponsive tty. Signals are ignored until suspended (Cmd+Z), 

```
$ build/src/cycript
cy# global
Target process terminated


^C^D
```

Expected value; global definitions in a list/ary or `ReferenceError` exception.

```
ie.
[1, 2, 3 ... global(n)] // definitons
```