ARROW-467: [Python] Run Python parquet-cpp unit tests in Travis CI
ARROW-467: [Python] Run Python parquet-cpp unit tests in Travis CI

This means we'll have to tolerate broken builds whenever APIs change (a good incentive to avoid changing them as much as possible)

Author: Wes McKinney <wes.mckinney@twosigma.com>

Closes #311 from wesm/ARROW-467 and squashes the following commits:

a9c285d [Wes McKinney] parquet-cpp build tweaks
661671c [Wes McKinney] Build parquet-cpp from source and run PyArrow Parquet unit tests in Travis CI

dremio/arrow,wagavulin/arrow,pcmoritz/arrow,apache/arrow,NonVolatileComputing/arrow,pcmoritz/arrow,wagavulin/arrow,julienledem/arrow,majetideepak/arrow,cpcloud/arrow,TheNeuralBit/arrow,kou/arrow,yufeldman/arrow,majetideepak/arrow,renesugar/arrow,majetideepak/arrow,siddharthteotia/arrow,apache/arrow,xhochy/arrow,wesm/arrow,julienledem/arrow,apache/arrow,xhochy/arrow,majetideepak/arrow,laurentgo/arrow,renesugar/arrow,StevenMPhillips/arrow,wesm/arrow,kou/arrow,pcmoritz/arrow,kou/arrow,yufeldman/arrow,xhochy/arrow,apache/arrow,NonVolatileComputing/arrow,majetideepak/arrow,wesm/arrow,wagavulin/arrow,apache/arrow,itaiin/arrow,laurentgo/arrow,wesm/arrow,icexelloss/arrow,pcmoritz/arrow,xhochy/arrow,tebeka/arrow,jeffknupp/arrow,NonVolatileComputing/arrow,julienledem/arrow,icexelloss/arrow,siddharthteotia/arrow,kou/arrow,xhochy/arrow,renesugar/arrow,NonVolatileComputing/arrow,majetideepak/arrow,xhochy/arrow,dremio/arrow,pcmoritz/arrow,jeffknupp/arrow,wagavulin/arrow,cpcloud/arrow,wesm/arrow,pcmoritz/arrow,pcmoritz/arrow,StevenMPhillips/arrow,yufeldman/arrow,siddharthteotia/arrow,cpcloud/arrow,laurentgo/arrow,wagavulin/arrow,dremio/arrow,itaiin/arrow,NonVolatileComputing/arrow,julienledem/arrow,xhochy/arrow,TheNeuralBit/arrow,majetideepak/arrow,NonVolatileComputing/arrow,wesm/arrow,jeffknupp/arrow,jeffknupp/arrow,kou/arrow,jeffknupp/arrow,wesm/arrow,majetideepak/arrow,laurentgo/arrow,wagavulin/arrow,majetideepak/arrow,julienledem/arrow,apache/arrow,pcmoritz/arrow,renesugar/arrow,icexelloss/arrow,kou/arrow,pcmoritz/arrow,renesugar/arrow,xhochy/arrow,itaiin/arrow,StevenMPhillips/arrow,StevenMPhillips/arrow,NonVolatileComputing/arrow,laurentgo/arrow,itaiin/arrow,cpcloud/arrow,apache/arrow,dremio/arrow,renesugar/arrow,majetideepak/arrow,NonVolatileComputing/arrow,siddharthteotia/arrow,siddharthteotia/arrow,renesugar/arrow,yufeldman/arrow,renesugar/arrow,icexelloss/arrow,kou/arrow,pcmoritz/arrow,wesm/arrow,kou/arrow,dremio/arrow,laurentgo/arrow,renesugar/arrow,wesm/arrow,laurentgo/arrow,tebeka/arrow,cpcloud/arrow,xhochy/arrow,siddharthteotia/arrow,StevenMPhillips/arrow,julienledem/arrow,siddharthteotia/arrow,NonVolatileComputing/arrow,itaiin/arrow,laurentgo/arrow,yufeldman/arrow,pcmoritz/arrow,kou/arrow,icexelloss/arrow,icexelloss/arrow,TheNeuralBit/arrow,siddharthteotia/arrow,siddharthteotia/arrow,yufeldman/arrow,pcmoritz/arrow,pcmoritz/arrow,apache/arrow,tebeka/arrow,icexelloss/arrow,laurentgo/arrow,renesugar/arrow,cpcloud/arrow,wesm/arrow,yufeldman/arrow,cpcloud/arrow,xhochy/arrow,apache/arrow,kou/arrow,cpcloud/arrow,itaiin/arrow,TheNeuralBit/arrow,apache/arrow,apache/arrow,laurentgo/arrow,kou/arrow,itaiin/arrow,pcmoritz/arrow,renesugar/arrow,wesm/arrow,cpcloud/arrow,siddharthteotia/arrow,dremio/arrow,majetideepak/arrow,NonVolatileComputing/arrow,jeffknupp/arrow,laurentgo/arrow,icexelloss/arrow,itaiin/arrow,wagavulin/arrow,majetideepak/arrow,wesm/arrow,cpcloud/arrow,tebeka/arrow,kou/arrow,cpcloud/arrow,wagavulin/arrow,tebeka/arrow,renesugar/arrow,dremio/arrow,yufeldman/arrow,wagavulin/arrow,NonVolatileComputing/arrow,majetideepak/arrow,laurentgo/arrow,jeffknupp/arrow,renesugar/arrow,itaiin/arrow,icexelloss/arrow,itaiin/arrow,laurentgo/arrow,StevenMPhillips/arrow,icexelloss/arrow,siddharthteotia/arrow,julienledem/arrow,dremio/arrow,dremio/arrow,tebeka/arrow,wagavulin/arrow,TheNeuralBit/arrow,dremio/arrow,jeffknupp/arrow,majetideepak/arrow,xhochy/arrow,cpcloud/arrow,renesugar/arrow,jeffknupp/arrow,xhochy/arrow,dremio/arrow,yufeldman/arrow,xhochy/arrow,tebeka/arrow,yufeldman/arrow,icexelloss/arrow,julienledem/arrow,tebeka/arrow,StevenMPhillips/arrow,icexelloss/arrow,StevenMPhillips/arrow,tebeka/arrow,renesugar/arrow,itaiin/arrow,apache/arrow,StevenMPhillips/arrow,tebeka/arrow,julienledem/arrow,yufeldman/arrow,wagavulin/arrow,laurentgo/arrow,apache/arrow,wagavulin/arrow,icexelloss/arrow,cpcloud/arrow,xhochy/arrow,laurentgo/arrow,cpcloud/arrow,wesm/arrow,itaiin/arrow,wesm/arrow,jeffknupp/arrow,itaiin/arrow,kou/arrow,majetideepak/arrow,apache/arrow,kou/arrow,icexelloss/arrow,itaiin/arrow,jeffknupp/arrow,StevenMPhillips/arrow,itaiin/arrow,xhochy/arrow,pcmoritz/arrow,TheNeuralBit/arrow,julienledem/arrow