Merge tag '0.6.0-beta.7' into develop

pallet-lein-0.6.0-beta.7
Updated version for next release cycle
Update classpath wording in README
Remove sonatype from project.clj
Update to pallet 0.8.0-beta.6
Correct group-id in dev profile
Updated project.clj, release notes and readme for 0.6.0-beta.8
Merge branch 'release/0.6.0-beta.8'