Remove uses of std::endl, which imply a flush
Make `def` more efficient, fix to_string(string)
Add fun_call_performance samples
Merge branch 'performance_evaluations' into performance_test
Speed up print functions
Add object lifetime test that failed in v5.4.0
Merge branch 'add_object_lifetime_test' into develop
Fix stack memory management

From 747M to 6.2M for profiling tests.
Merge branch 'develop' into performance_test
Reworking of binary operators

- Eliminates re-parsing of operator strings
- Reduces much redundant code

Results

1. smaller binaries
2. less runtime memory usage
4. faster runtime
Clean up Prefix() implementation

Reducing redundant code
Reduce redundant parsing / error code
Work around bug in gcc 4.6 for initializer_list

Hopefully also fixes MSVC 2012
Clean up compiler warnings
Merge remote-tracking branch 'origin/develop' into performance_test
Remove extraneous std::cout messages
Put to use new skip_packaging and build_tag features
Add "skip_packaging" to macos debug build
Only package 4.8 gcc on linux
Skip packaging of MSVC 14 builds