Revert "DIsable caching for mac"

This reverts commit a1ff9613
7 jobs for ci_mac in 66 minutes and 52 seconds
Status Name Job ID Coverage
  Test
passed clang-c++11-Qt5 #15925
Linux MultiThreads

00:09:00

passed cppcheck #15926
Linux MultiThreads

00:36:40

passed gcc-c++11-Qt5 #15924
Linux

00:59:05

passed Mac-Cpp11 #15930
Apple

01:06:52

passed VS2013-Qt-5.5.1-x64 #15929
VS2013 Qt551

00:16:14

passed VS2015-Qt-5.6.0-x32 #15928
VS2015 Qt56

00:19:07

passed VS2015-Qt-5.6.0-x64 #15927
VS2015 Qt56

00:21:29