enhance configuration (#12, #15)

[amacado]

• Don't apply default config when custom config is provided #12 Don't apply default config when custom config is provided
• Add configuration for custom path of .yml configuration file #15 Add configuration for custom path of .yml configuration file

I decided to separate #11 "Configure using the with parameter" from this pull request since it is more complex and requires some more changes. Will see when I got some time to work on #11

[TimonVS]

Thanks so much! I left some feedback about the way the configuration path is provided :)

[amacado]

I will take a deeper look on your improvements and ideas @TimonVS, i'm quite busy at the moment so it can take a few days.

[TimonVS]

@amacado sure! Take your time :)

[TimonVS]

Hey @amacado, I was wondering if you still wanted to apply the changes. If not, please let me know so that I can apply them myself so that we can get this PR merged :)

[amacado]

Hey @TimonVS i was suffering a heavy cold the last two weeks and since it's my first day back in job I have a ton of work todo. If u have the time feel free to apply the changes, I would need at least a couple more weeks.

[TimonVS]

Ah that's too bad about the cold :/, I hope you feel better soon!
I will probably apply the fixes myself sometime this week.