feat: allow any whitespace character to separate multiple styles (#226)

Currently it is impossible to use delimiters in styleName other than a single space symbol. The change allows to use any whitespace characters, such as a newline character which is handy if you use multiple class names in a single styleName attribute combined with ES6 string literal.

src/parseStyleName.js

@@ -8,7 +8,7 @@ export default (styleNamePropertyValue: string, allowMultiple: boolean): Array<s
   if (styleNameIndex[styleNamePropertyValue]) {
     styleNames = styleNameIndex[styleNamePropertyValue];
   } else {
-    styleNames = _.trim(styleNamePropertyValue).split(' ');
+    styleNames = _.trim(styleNamePropertyValue).split(/\s+/);
     styleNames = _.filter(styleNames);
 
     styleNameIndex[styleNamePropertyValue] = styleNames;