Do not use top for memory stats

The memory usage is being displayed incorrectly with top. vm_stat
produces the correct graph.
Remove one second delay after executing top
Display time remaining if running on battery
Add --[no]remaining option

- Display the time remaining until the battery is fully charged or
empty.  This will work on both OSX and Linux machines now.

- Update documention.
Fix OSX display issues using top

Creaktive created the patch. I simply ran git apply :)
Update readme
Add more conditions for displaying time on OSX

The remaining battery time will be displayed if:

- The battery is not fully charged, or

- The battery is not fully charged and it is plugged in, or

- The battery is fully charged and it is not plugged in
Add new screenshot to readme
Add new screenshot to readme
Specify terminal in screenshot
Modify usage of --remaining flag
Add caveat for --remaining option
Merge pull request #6 from jh3/master

Add option that will display the time remaining until the battery is fully charged/empty