add suppot for 2.8 log
added 2.8 level and component
fixes #269. fixes #270. changed '>= 2.4' to '= 2.4.x' and '>= 2.6' to '= 2.6.x'
Merge branch 'feature-269-2.7-plus-logging' of github.com:jimoleary/mtools into jimoleary-feature-269-2.7-plus-logging
improved help text for mlogfilter options.
only allow valid choices for mlogfilter options
Merge pull request #1 from rueckstiess/jimoleary-feature-269-2.7-plus-logging

improved mlogfilter help and only allow valid option choices
2.8 log file is actually for 2.7.8 and hand edited to add missing levels/components
meta-programming tests
2 more tests and reordered params
bug that prevented piping to mplotqueries.
Merge branch 'feature-269-2.7-plus-logging' of github.com:jimoleary/mtools into jimoleary-feature-269-2.7-plus-logging
Merge branch 'jimoleary-feature-269-2.7-plus-logging' into develop