Fix minor issues

Fix clang format detection

common: replace 'C' headers with equivalent 'C++' headers for C++ specific files

add next_pow_2 common helper function

Add support for memcheck in external test dir

Add iterator_traits header file with tests

Standard library does not provide public type traits to determine
if given iterator satsfies requirements of specyfic iterator type.
This commit provide such a type traits with tests.

fix cmake's if condition

Fix cmake CGDB usage

Add 1.5 changelog

Klockwork fixes

Because no custom copy ctor/operator was provided copying ctree map
could result in double free.

previously only files passed to add_example were being checked.
This means that all .hpp files were omitted.

which were not added by add_cppstyle

Minor fixes

and reformat those tests

to silence klockwork

common: add missing @file annotations

common: unify include guards

common: create version.hpp file

and names of common files in examples

Find package refactoring