#117 fix SPI tests by adding missing key/value type checks
 #117 move SPI test methods so we're DRY-ready once other Store implementations are on the way
 #117 fix wrongValueTypeThrowsException to make it check the value type and not the key type
Merge pull request #123 from lorban/issue-117

 #117 fix SPI tests by adding missing key/value type checks
Issue #75: wired CacheLoader where applicable.
Issue #75: corrected method signatures to include CacheLoader/CacheWriter exceptions where applicable.
Issue #75: split fix for OnHeapStore.bulkComputeIfAbsent() from main commit.
Merge pull request #121 from vfunshteyn/issue-75

Issue #75: wired CacheLoader where applicable.
Added some API example, both in code and in README.adoc
Added explanation section on the current work and milestone targets
Linked straight to code in github
Merge pull request #124 from alexsnaps/Doc

Added some API example, both in code and in README.adoc
Fixed relative links to work on github
Got rid of relative links

but for the "forward only pointing" one