Bug reports: create "logs" folder and populate it at each run (#500)

* Bug reports: create "logs" folder and populate it at each run

This makes it easier for people to open issues
as we will ask them to attach every file in the "logs" folder.

File have the .txt extension so they can easily be
drag & dropped into gihub issues

For Arch people: to obtain the shell-output.log, we will ask them to do it
by hand:

makepkg [args] | tee shell-output.log

Signed-off-by: Adel KARA SLIMANE <adel.ks@zegrapher.com>

* prepare: cleanup "logs" folder at each run

So some files, that usually get appended to, don't
grow to infinity.

This behavior needs to be changed if we decide to
keep more logs than the latest one.

Signed-off-by: Adel KARA SLIMANE <adel.ks@zegrapher.com>

update-kernel-versions.sh

@@ -13,6 +13,7 @@ kernel_tags=$(git -c 'versionsort.suffix=-' \
     | cut --delimiter='/' --fields=3)
 
 source linux-tkg-config/prepare
+trap - EXIT
 
 updates=""
 for _key in "${_current_kernels[@]}"; do