Better ControlSpacesFixer multiline indentation.

Before this fix, ControlSpacesFixer lost the indentation of multiline
if -control statement for outer closing parenthesis.

Before:
<pre>
        if(true === true
            && false === false
        ) {
</pre>
Became:
<pre>
        if (true === true
            && false === false
) {
</pre>

Now:
<pre>
        if (true === true
            && false === false
        ) {
</pre>

Also commented the regular expression with inline comment, so it's
easier to understand.

In ControlSpacesFixer::fixControlsWithParenthesesAndSuffixBrace()
<pre>(%s)[^\S\n]*\([^\S\n]*([^()]*?|(?R))[^\S\n]*\)[^\S\n]*{</pre>
Became:
<pre>(%s)[^\S\n]*\([^\S\n]*([^()]*?|(?R))[^\S\n]*(\s*)\)[^\S\n]*{</pre>