Some Macs don't  reach the max battery capacity

Checking ioreg for "FullyCharged" to be set to "Yes" and that's it's
connected to power; if so don't display segment. Also dropped the max
percentage to 99% (some older machines don't reach 100% charge
capacity).
Merge pull request #165 from ericboehs/master

Some Macs don't reach their max battery capacity