Removes the old error handling library and switches to plain
fmt.Errorf calls.
There are several reasons for this:
* There are no useful types or handling here anyways, so output format
is the only priority.
* Users don't care about getting stacktraces.
* My emotional wellbeing.
Fin de siècle.
This is actually several refactors in one:
* rename "fileContent" function to "insertFile"
* pass the resource set path to the "insetFile" function
* update docs and example with a pipeline including indentation
adjustments for the inserted file
Adds a 'fileContent' template function to insert the literal contents
of a file specified in the template.
Signed-off-by: Niklas Wik <niklas.wik@nokia.com>
This introduces support for looking up secret values in the 'pass' command line
tool (https://www.passwordstore.org/).
Values like passwords can be interpolated from pass and even more complex
structures like certificates for Kubernetes Secrets can be retrieved and base64-
encoded as necessary.
Fixes#2
