fix: deb: create subfolders and use GNU tar format

[caarlos0]

closes #6

tl;dr: the problem was in the data.tar.gz, which had only the files, but not the folders themselves.

I had to walk through the desired path and create the headers inside the tar file, which fixes the issue as it seems.

drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/bin/
-rwxr-xr-x  0 0      0     1034959 Feb 25 14:58 usr/bin/rclone
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/doc/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/doc/rclone/
-rw-r--r--  0 0      0        3267 Feb 25 14:58 usr/share/doc/rclone/README.txt
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/man/
drwxr-xr-x  0 0      0           0 Dec 31  1969 usr/share/man/man1/
-rw-r--r--  0 0      0      355170 Feb 25 14:58 usr/share/man/man1/rclone.1

before that , we had:

-rwxr-xr-x  0 0      0     1034959 Feb 25 14:58 usr/bin/rclone
-rw-r--r--  0 0      0        3267 Feb 25 14:58 usr/share/doc/rclone/README.txt
-rw-r--r--  0 0      0      355170 Feb 25 14:58 usr/share/man/man1/rclone.1

as a bonus, I also changed the format of the headers to GNU format.

---

TODO:

• avoid duplicating the paths (usr/ header is added several times)
• betere cover it with tests

[codecov-io]

Codecov Report

Merging #8 into master will decrease coverage by 5.65%.
The diff coverage is 84.9%.

@@            Coverage Diff             @@
##           master       #8      +/-   ##
==========================================
- Coverage   71.53%   65.87%   -5.66%     
==========================================
  Files           3        4       +1     
  Lines         274      337      +63     
==========================================
+ Hits          196      222      +26     
- Misses         39       74      +35     
- Partials       39       41       +2

Impacted Files	Coverage Δ
deb/deb.go	73.68% <84.9%> (+3.19%)	⬆️
cmd/nfpm/main.go	0% <0%> (ø)

---

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[caarlos0]

drwxr-xr-x  0 0      0           0 Feb 25 17:35 usr/
drwxr-xr-x  0 0      0           0 Feb 25 17:35 usr/bin/
-rwxr-xr-x  0 0      0     1034959 Feb 25 17:35 usr/bin/rclone
drwxr-xr-x  0 0      0           0 Feb 25 17:35 usr/share/
drwxr-xr-x  0 0      0           0 Feb 25 17:35 usr/share/doc/
drwxr-xr-x  0 0      0           0 Feb 25 17:35 usr/share/doc/rclone/
-rw-r--r--  0 0      0        3267 Feb 25 17:35 usr/share/doc/rclone/README.txt

looks great now!

[caarlos0]

λ docker run -v $PWD:/tmp -it ubuntu dpkg -i /tmp/rclone.deb
Selecting previously unselected package rclone.
(Reading database ... 4768 files and directories currently installed.)
Preparing to unpack /tmp/rclone.deb ...
Unpacking rclone (1.39) ...
Setting up rclone (1.39) ...

[caarlos0]

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.