Peter M. Groen / CLI11

* Overflowing an integer conversion now results in a conversion failure

* CMake improvements for VERSION and inital packing support

* Fix for recent addition of overflow check

* Conan file now gets version from Version.hpp file too

* Split signed/unsigned parsing, add check if input is fully consumed, improve tests

* Fix complex numbers parsing

* Add check if input is fully consumed for double lexical_cast, improve tests

* Add non-num non-string lexical_cast for parsable types, add tests

* Style fixes from check-style

* Some small fixes for corner case tests

* Adding fix for #75, rename requires to needs

* Removing check for install commands (should still be run in subproject)

* Support for unused (un-defined) extras in ini-files.

* Fixed extra options in INI files to be closer to that of extra CLI arguments.

* Fixed formatting.

* Minor formatting fix.

* Fixing style

* Fixed INHERITABLE and other minor things.

Some error codes are renamed

[skip ci]