PATH arguments listed twice when backup is created

[jpellenz]

Steps to reproduce:

1. Create a borgbackup.ini file with PATH entries:
   ...
   PATH = /tmp/project
   PATH = /tmp/project2
   ...

2. Create a backup

• ./borgctl backup ./borgbackup.ini

3. Expected behavior

• elements in path are listed once

4. Actual behavior

• elements in path are listed twice:
  -+> BACKUP for 001 ...
  -+> borg create -s -v --list -C zlib,6 ::tftp-201803162311170100 /BACKUP//tmp/project /BACKUP//tmp/project2 /BACKUP//tmp/project /BACKUP//tmp/project2
  U /BACKUP/tmp/project/test1.txt
  U /BACKUP/tmp/project/test2.txt
  d /BACKUP/tmp/project
  A /BACKUP/tmp/project2/test1.txt
  A /BACKUP/tmp/project2/test2.txt
  d /BACKUP/tmp/project2
  U /BACKUP/tmp/project/test1.txt
  U /BACKUP/tmp/project/test2.txt
  d /BACKUP/tmp/project
  U /BACKUP/tmp/project2/test1.txt

5. Probably the problem is in the BACKUPS[PATH${id}] contruction in help_init_from_ini():

In help_init_from_ini():

 ...
                            if [[ "$2" == "PATH" ]]; then
                                    BACKUPS[PATH${id}]="${BACKUPS[PATH${id}]} ${3}"
                            fi
 ...

Since help_init_from_ini() is called multiple times (from docker_compare_host_container_script() and docker_set_borg_repo()), the BACKUPS[PATH${id}] is extended twice by the PATH arguments.

[jpellenz]

Seems to be a side effect from commit c2f53a3 where the second call to help_init_from_ini() was introduced.