Moving MAKE_HELPER macro out of operator
Fix include gaurd ofr goldbar and logsqrt2pi generative
if_else for logical types added to common
separate case for GCC mask load removed from common load.hpp as if else now accounts for logical types
if_else added to common for arithmetic logical logical
additional unit tests added to if_else simd
Small fixes on if_else
removing unused variables in gammaln
includes had not been cleaned in euler
changing bounds to anp cover to fit 0 ulp tets.
For n =15 p =6 float computating are not more exact (2 ulps)
anp and cnp are no more defined for integers benches are modified accordingly
change name of generic memory unit tests
Merge pull request #738 from jtlap/gammaln_incs

Gammaln incs
Quick-fix for failed gather_includes builds when cross compiling (missing exceptions support).
Applied the same quick-fix to move_reuse and postconfigure as for gather_includes.
(note to nt2 devs: there seems to be duplication between the CMakeLists.txt files for the three tools)
Fixed/updated remaining code affected by the timing code changes.
Added attempts to prevent the compiler and/or the CPU from reordering and/or removing calls to timing functions.
Changed the default time unit to microseconds.
Added and used the priority_booster_t utility class.
Added more todo and implementation notes.
Further improved stability/accuracy of the timing functions overhead (still not "perfect", especially for now()).
Optimized the median<>() function template and (temporarily) moved it into the now.cpp.
Switched to the rand48 PRNG (as it is faster) and (temporarily) moved the reusable PRNG functions into the now.cpp.
Minor other refactoring and stylistic changes.
Created a virtual interface class for benchmarks. Used it to make the perform_benchmark function a non template and (temporarily) moved it to now.cpp.
Used the perform_benchmark(_impl) function in now.cpp to accurately calculate the timing functions overhead (this now produces stable/reproducible results).
Minor CT optimization.
Added "beta"/"prototype" support for GCC's bultin vector type.
Added a workaround for a GCC performance bug related to bultin_unreachable.
Minor other reafactoring and stylistic changes.