Removed executables line from gemspec

We don't have any executables to worry about
Version 0.5.0
Merged 0.4.7 and 0.5.0 changelog notes

Turns out 0.4.7 was never actually released!
DRY spec
Implement multiple goals for an experiment
rebase from upstream/master
DRY spec
fix some bugs
remove default goal
update readme
rename variants to alternatives
Merge pull request #109 from coolzilj/master

Allows An Experiment To Have Multiple Goals
Added more known bots to the default configuration
Added pingdom to bot list
Merge pull request #113 from julesie/master

Adding Pingdom to Bot List
Don't test on REE for the moment, it's broken on travis
Update Readme to match e7a893c
Merge pull request #114 from iangreenleaf/readme_update

Update Readme to rename "variants" to "alternatives"
Failing test for a regression with config files
Pull config file fallback out of nested methods

It needs to happen earlier so that fallbacks to the control will succeed.

This may not be the most sensible code organization.