Make Installation more noob friendly

[Torstein-Eide]

No description provided.

[kilobyte]

Thank you for your effort, but I'm going to decline this.

• distributions provide this package on a timely basis
• without packages, there's no easy way to uninstall
• using /bin instead of correctlier /usr/bin or correctest /usr/sbin makes such hand-copied binary silently override packaged version
• so would FHS-compliant /usr/local/sbin
• the program is unpolished and aimed at filesystem developers and sysadmins. At least some level of btrfs knowledge is expected, and that implies knowing basic Unix ways.

[Torstein-Eide]

Hi @kilobyte
I have updated the PR to reflect that compsize is available via repository.