cleaned up SettingsOperation
cleaned up access/RadixCluster
Distinguish Union and UnionAll

This moves the expected behavior from UnionScan to UnionAll.
Union will remove duplicate positions while UnionAll will not.
Remove code comments from PlanOperation
cleaned up access/PrefixSum
cleaned up access/MergeHashTables
cleaned up access/RadixJoin
cleaned up access/NestedLoopEquiJoin
cleaned up access/Barrier
Merge pull request #85 from timbokopter/feature/cleanup_RadixJoin

cleaned up access/RadixJoin
Merge pull request #60 from timbokopter/feature/cleanup_SettingsOperation

cleaned up SettingsOperation
Merge pull request #87 from timbokopter/feature/cleanup_Barrier

cleaned up access/Barrier
Merge pull request #83 from timbokopter/feature/cleanup_PrefixSum

cleaned up access/PrefixSum
Merge pull request #84 from timbokopter/feature/cleanup_MergeHashTables

cleaned up access/MergeHashTables
Merge pull request #77 from timbokopter/feature/cleanup_RadixCluster

cleaned up access/RadixCluster
Merge pull request #86 from timbokopter/feature/cleanup_NestedLoopEquiJoin

cleaned up access/NestedLoopEquiJoin
Add binutils-dev to hyrise recipe.

Fixes #89
Merge branch 'master' of github.com:hyrise/hyrise
Merge pull request #81 from bastih/feature/Distinguish_Union_and_UnionAll

Distinguish Union and UnionAll
remove check for duplicate inputs; issue #88