Apply formatting/style tweaks to comply with compile time diagnostics for g++ and clang++ (#686)

* Add compilation flags: -Wshadow -Weffc++ -pedantic -pedantic-errors
* Delete implicit copy & move constructors & assignment operators
  in classes with pointer data members.
* An exception to the above: Add default copy & move constructors &
  assignment operators for the Binary class.
* Convert boolean RegEx operators to binary operators.
* Initialize all members in all classes in ctors.
* Let default ctor delegate to the converting ctor in
  Binary and RegEx
* Don't change any tests except regex_test (as a result of the change
  to binary operators).

Note: https://bugzilla.redhat.com/show_bug.cgi?id=1544675 makes
-Weffc++ report a false positive in "include/yaml-cpp/node/impl.h".

CMakeLists.txt

@@ -165,7 +165,7 @@ if(CMAKE_CXX_COMPILER_ID MATCHES "GNU" OR
 		set(GCC_EXTRA_OPTIONS "${GCC_EXTRA_OPTIONS} -fPIC")
 	endif()
 	#
-	set(FLAG_TESTED "-Wextra")
+	set(FLAG_TESTED "-Wextra -Wshadow -Weffc++ -pedantic -pedantic-errors")
 	check_cxx_compiler_flag(${FLAG_TESTED} FLAG_WEXTRA)
 	if(FLAG_WEXTRA)
 		set(GCC_EXTRA_OPTIONS "${GCC_EXTRA_OPTIONS} ${FLAG_TESTED}")