sjjaffe/cpp-argument-parser @ 0.6

Sam Jaffe 06275fe60a Add test coverage		4 anni fa
..
argument_test.cpp	fb2626a821 Cover the rest of the usecases for arguments.	4 anni fa
flag_test.cpp	d8af8f0c92 Adding more tests.	4 anni fa
options_test.cpp	28c9b19de7 Test repeatable arguments.	4 anni fa
usage_test.cpp	06275fe60a Add test coverage	4 anni fa
xcode_gtest_helper.h	f36d481b18 Perform some cleanup, add some test skeletons.	4 anni fa