- Some of values were not converted back from base64, which resulted in
spurious errors with base64 strings.
(This was caused by nested arrays, like commands, not being converted
back, combined with the wrong assumption that commands always occur
before options. It is not always true, as the added test case
demonstrates.)
- Some other values were converted *from* base64, but they weren't
base64 in the first place, which resulted in junk binary data.
(This was due to the invalid assumption that only odd-numbered values
need to be converted.)
- fixed the tests when `SLS_IGNORE_WARNING` is set in the shell environment
- refactored the tests to clearly expose the tested input combinations (+ added the missing combination - to have a formally complete verification)
- added the `SLS_IGNORE_WARNING=*` setting to Travis builds, so that their output doesn't contain unnecessary noise about upcoming changes
