(FACT-695) Return correct data types

Fix the processorcount, physicalprocessorcount, *_mtu, is_virtual,
selinux, mem*_mb, swap*_mb and sp_* facts for return the correct data
types. Mostly integers or booleans instead of strings.
(FACT-695) Update schema to new fact data types
Merge pull request #777 from dalen/695-data-types

(FACT-695) Return correct data types