[WIP] [feature] StructureBracesFixer

Braces for structure blocks, fix #98

- [x] add missing braces
- [x] correct single-level intend
- [ ] correct multi-level intend
- [ ] fix #168 
- [ ] make Travis pass
It seems that I was the first at this project who start using reverse iteration and yes, I do not use it here knowingly.

Let's take a look:
original code:
```if (true) { if (false) { echo 1; } }```

Looking forward:
1 iteration
```
if (true) {
    if (false) { echo 1; }
}
```
2 iteration
```
if (true) {
    if (false) {
        echo 1;
    }
}
```

Looking backward:
1 iteration
```
if (true) { if (false) {
    echo 1;
} }
```
2backward
```
if (true) {
    if (false) {
    echo 1;
    }
}
```


Looking forward gives better results for this fixer.
But as mentioned in todo list - indenting is not complete yet, so it will may changed.