Space in section header

Consider the following

```
[REPLICA_SET] 
additional_directories = ['${JSONAR_LOCALDIR}/credentials', '${JSONAR_DATADIR}/sonarfinder/reports']
```

This crashes the parser.

If I were to patch:

```
const SECTION = new RegExp(/^\s*\[([^\]]+)]$/);
```

to

```
const SECTION = new RegExp(/^\s*\[([^\]]+)]\s*$/);
```

this fixes the problem.