Better ControlSpacesFixer multiline indentation.

Before this fix, ControlSpacesFixer lost the indentation of multiline
if -control statement for outer closing parenthesis.

Before:
        if(true === true
            && false === false
        ) {
Became:
        if (true === true
            && false === false
) {

Now:
        if (true === true
            && false === false
        ) {

Commit also comments the regular expression with inline comment, so it's
easier to understand.

In ControlSpacesFixer::fixControlsWithParenthesesAndSuffixBrace()
(%s)[^\S\n]*\([^\S\n]*([^()]*?|(?R))[^\S\n]*\)[^\S\n]*{
Became:
(%s)[^\S\n]*\([^\S\n]*([^()]*?|(?R))[^\S\n]*(\s*)\)[^\S\n]*{