JustFetch

1. Optimized how uptime is fetched. It's now using /proc/uptime rather than an expensive execute / Command call.

1. Added a new alias: used_mem

1. Optimized the code to utilize more libc calls, rather than parsing from a Command instance.
   • Before: ~6/8ms of execution time, now: ~2-4ms of execution time. Quickly measured using time so the values may fluctuate.
2. Added mem aliases

Optimized the code even further by utilizing libc calls.

First initial release.