use s3 configuration loader
remove bad key
move to class-based singletons
POM FIXES

- remove all conflicts
- fix a common s3 uploader error case
handle common error case
checkstyle fixes
remove commons-lang 2.x dependency

In the ongoing quest to eradicate commons-lang 2.x from the face of
the earth, make Singularity use commons-lang3 everywhere.
checkstyle fixes, round 2
Merge pull request #217 from hgschmie/commons-lang

remove commons-lang 2.x dependency
Merge pull request #215 from hgschmie/checkstyle

checkstyle fixes
Merge pull request #4 from HubSpot/master

Merge from Hubspot