added forIn, getBytes for supporting ie8

added 2 util functions (forIn, getBytes).
- forIn : ie8 ignores constructor property in "for .. in" loop. this function would be used also in Spine.
- getBytes : it would be used in Match Breakdown for calculating the correct offset of pie chart title (such as 'Champion Kills', 'Gold Earned') not only 1byte character but also 2bytes character.


i'm not sure i understand what you're saying but if i'm right, this is not for bypassing `hasOwnProperty` call.
In ie8, `constructor` property is not caught by javascript `for .. in` loop. so `if(!hasConstructor && obj.hasOwnProperty(filterKey))` is a kind of failover.

at first, i thought it would be better make change `onBeforeCreated` directly but i noticed [here](https://gh.riotgames.com/rchung/Spine/blob/master/src/spine/ux/Marionette.js#L178-L186) should be also changed, so extracted it.

is it better way to change Marionette.js too? or should i rewrite the code for readability?
please let me know what do you think.