Bugfixes (#13)

* several fixes:

- fix #9 + #10: switched to koanf module and dropped support for HCL
- fix #11: disabling colors on windows
- fix #12: fixed race condition in go routine call inside for loop,
  images had been downloaded multiple times
- remove hcl support and use toml format (same thing, better parser)
- update documentation and example config on TOML format of config file
- use Config as arg instead of singular args
- use x/errgroup instead of sync.Waitgroup inside image download loop

---------

Co-authored-by: Thomas von Dein <tom@vondein.org>

kleingebaeck.pod

@@ -4,16 +4,18 @@ kleingebaeck - kleinanzeigen.de backup tool
 
 =head1 SYNOPSYS
     
-    This is kleingebaeck, the kleinanzeigen.de backup tool.
     Usage: kleingebaeck [-dvVhmoc] [<ad-listing-url>,...]
     Options:
-    --user,-u <uid>        Backup ads from user with uid <uid>.
-    --debug, -d            Enable debug output.
-    --verbose,-v           Enable verbose output.
-    --output-dir,-o <dir>  Set output dir (default: current directory)
-    --manual,-m            Show manual.
-    --config,-c <file>     Use config file <file> (default: ~/.kleingebaeck).
-    
+    --user    -u <uid>      Backup ads from user with uid <uid>.
+    --debug   -d            Enable debug output.
+    --verbose -v            Enable verbose output.
+    --outdir  -o <dir>      Set output dir (default: current directory)
+    --limit   -l <num>      Limit the ads to download to <num>, default: load all.
+    --config  -c <file>     Use config file <file> (default: ~/.kleingebaeck).
+    --manual  -m            Show manual.
+    --help    -h            Show usage.
+    --version -V            Show program version.
+
 =head1 DESCRIPTION
 
 This tool can be used to backup ads on the german ad page L<https://kleinanzeigen.de>.
@@ -25,23 +27,38 @@ title, body, price etc. All images will be downloaded as well.
 
 =head1 CONFIGURATION
 
-You can create a config file to save typing. By default
-C<~/.kleingebaeck.hcl> is being used but you can specify one with
-C<-c> as well.
+You   can  create   a  config   file  to   save  typing.   By  default
+C<~/.kleingebaeck> is being used but you can specify one with C<-c> as
+well.   We    use   TOML   as   our    configuration   language.   See
+L<https://toml.io/en/>.
 
-Format is simple:
+Format is pretty simple:
 
     user = 1010101
-    verbose = true
+    loglevel = verbose
     outdir = "test"
-    template = ""
+    template = """
+    Title: {{.Title}}
+    Price: {{.Price}}
+    Id: {{.Id}}
+    Category: {{.Category}}
+    Condition: {{.Condition}}
+    Created: {{.Created}}
 
-Be carefull if you want to change the template. The default one looks like this:
+    {{.Text}}
+    """
 
-   Title: {{.Title}}\nPrice: {{.Price}}\nId: {{.Id}}\nCategory: {{.Category}}\nCondition: {{.Condition}}\nCreated: {{.Created}}\n\n{{.Text}}\n
+Be carefull  if you want  to change the  template.  The variable  is a
+multiline string surrounded  by three double quotes. You  can left out
+certain   fields  and   use  any   formatting  you   like.  Refer   to
+L<https://pkg.go.dev/text/template>  for   details  how  to   write  a
+template.
 
-You can left out certain fields and use any formatting you like. Refer
-to L<https://pkg.go.dev/text/template> for details how to write a template.
+If you're on  windows and want to customize the  output directory, put
+it into single  quotes to avoid the backslashes  interpreted as escape
+chars like this:
+
+    outdir = 'C:\Data\Ads'
 
 =head1 SETUP