#13355 - Uglifyjs compression options and variable sequence optimization 

<ol>
<li>Some Uglifyjs options might work great for minification, but worsens gzip size, disabling these options will increase minified size but decrease gzipped one, </li>
<li>Sometimes changing sequence of variables initialization might save couple of bytes in gzipped size, in this PR, i also propose find optimal sequences of those variables that don't have an assigment. I did it with limitation of 7 items in sequence, i.e. <a href="https://github.com/jquery/jquery/blob/master/src/event.js#L130-132">here</a> is 11 variables with initialization value of undefined, so all possible permutations for variables without an assigment is 39916800, i checked only 5040 of them. </li>
</ol>
Same optimizations could be applied to 2.0 source and for variables with (re)assigment but i did not finish AST analysis for those possibilities.

Anyway, for 1.9 current gzipped size is 33006 bytes, in this branch it's 32642, all and all it's -346 bytes for gzipped size.