Encoding Numeric Strings

[rodnaph]

Fix for encoding numeric values in strings.

Current behaviour is saving the value "1" into the FileSystem cache will detect it as numeric and actually store the integer 1. This updates that behaviour to return the original string.

[coveralls]

Coverage decreased (-0.009%) to 95.048% when pulling 858f9a3 on owsy:encode-numeric-string into a6f14f7 on tedious:master.