Incorrect composition of rules when using * selector

[FatConan]

Hi,
I believe I've found that the rules being generated when using the * selector can introduce white space that alters the meaning of the rule.

Below you can see the outputs of running a quick test from the shell (running version 0.15.1 of lesscpy). You can see that specifying div:last-child lesscpy correctly generates the rule as div.test>div:last-child, however, using *:last-child introduces white space that alters the meaning of the rule, outputting div.test>* :last-child.

>>> import lesscpy
>>> from six import StringIO
>>>
>>> print(lesscpy.compile(StringIO(u"div.test > *:last-child { border-width: 2px * 3; }"), minify=True)) 
div.test>* :last-child{border-width:6px;}
>>> print(lesscpy.compile(StringIO(u"div.test > div:last-child { border-width: 2px * 3; }"), minify=True)) 
div.test>div:last-child{border-width:6px;}