[Feature] Add aliases

[teobais]

• Clear git history (consult: https://gist.github.com/stephenhardy/5470814)
• check for how long a process has been running
• tracking/untracking git files
• git stash save "bladi blah"

Details

check for how long a process has been running
Example for process with a PID of 96109: ps -p "96109" -o etime=
The output will be like 02-08:51:24 <- [[dd-]hh:]mm:ss
Also examine the possibility of formatting the preceding output into columns or better format.

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tracking/untracking git files
untrack git update-index --assume-unchanged path/to/file
track again git update-index --no-assume-unchanged path/to/file

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