* ValidatePositions can now be used with Stores
  * GroupByScan without Hashing for ops without grouping
  * Fixing bug in tablebuilder that would build a wrong layout, but correct view on top of it
  * Fixing default merge settings in Store, to not use compression
  * Made the code compiling without precompiled headers by including the necessary includes
Merge pull request #176 from hyrise/feature/updates_to_querying_in_tx

Feature/updates to querying in tx
Added Metadata Operator with documentation and tests
Merge pull request #188 from irruputuncu/master

Added MetaData Operator with docs and test
tpccTableLoadTest.cpp now looks less copy-paste like
Merge pull request #190 from kateyy/tpccTableLoadTest

refactored TpccTableLoadTest
adding Operations to GroupByScan
* >as< to specify the name of the resulting aggregation column
* >min< and >max< as new operators
* >distinct< option for count operator (naive distinct algorithm)
* unit test for empty tables
Merge pull request #152 from lordgeorg/groupby_ops

adding Operations to GroupByScan
* >as< to specify the name of the resulting aggregation column
* >min< and >max< as new operators
* >distinct< option for count operator (naive distinct algorithm)
* unit test for empty tables
Merge branch 'master' into feature/new_mvcc

Conflicts:
	src/bin/units_access/tx_tests.cpp