added json detailed report

added json format builder

cleaned up command description, added string output info to README, added UnitTest for Json report

cleanup, reworked json to get detailed stats

finished json detailed report, fixed according unittest, added optional pretty printing for result checking

fixed command help to reflect type of report correctly
Merge pull request #37 from maschmann/feature/json_output

phpci integration #36
fixes errors in #37
fixes #38 : default configuration is now loaded
minor : ConfigurationInterface added
metrics.phar is now phpmetrics.phar
-m
phpmetrics.php is now phpmetrics
documentation of command line usage : fixes #35
update test of cli usage
phpmetrics ignore more directories by default : vendir, .git, .svn
link to documentation
typo in README