Fix for documentation reader not being threadsafe

fixes issue #140
[maven-release-plugin] prepare release swagger-springmvc-0.6.3
[maven-release-plugin] prepare for next development iteration
Updated documentation
Merging from rel-0.6
[147] Fixing missing doco on controllers without top level @RequestMapping
Merge pull request #150 from adrianbk/rel-0.6

[147] rel-0.6 Fixing missing top level @RequestMapping issue

fixes #147
Added enforcer plugin to deterministically pick the versions
Merge branch 'rel-0.6'
[maven-release-plugin] prepare release swagger-springmvc-0.6.4
[maven-release-plugin] prepare for next development iteration
Updated readme
Merging from rel-0.6
Added credits section
Updated documentation for java configuration
Fixes NPE when return types are void

fixes #130, #139, #146
[maven-release-plugin] prepare release swagger-springmvc-0.6.5
[maven-release-plugin] prepare for next development iteration
Updated the documentation to 0.6.5
Merging from rel-0.6