Remove panic() from the codebase

[danielpaulus]

In a few places I used panic() back when I first wrote the code. I have come to the conclusion that panic and log.Fatal should not be used normally in library code. I want to search the code base for panic() and replace it with returning an error. Here is a good example for a small PR: https://github.com/danielpaulus/go-ios/blob/0fe0fcf2f1fd61d3275d36d1ce5e7a711e6c51c6/ios/nskeyedarchiver/archiver.go#L76

[snapdgn]

would be glad to take this up :)

[grokkos]

@danielpaulus is this still open to be picked?

[danielpaulus]

yeb. @grokkos still open.