This commit converts value to a property so that it
can be managed and modified when a file already has
a value set.
It was previously treating the line creation state
the same as the update case, which is not in
alignment with Puppet's model.
In order to allow the provider to be a parent for
other providers, I have implemented the following
methods: section, setting, file_path, separator so
that they can be overridden by child providers and
decouple this provider from its type.
This introduces a new parameter, 'key_val_separator', which
can be set in order to override the string that is used
as a separator between the key/value pair of a setting line.
The default is ' = ', but you could set the param to '=' if
you don't want to include whitespace in your settings file.
characters. Fixed writing to file without any sections at all.
Fixed exists checking for variable type by always casting to string
and added all the tests for the above items.
