Write packaging information

[onting]

For packaging, it's supposed to write metadata for it.
Generally, cpack generater generates various installer as long as ConfigVersion.cmake is written or could be generated from CMakeConfigHelpers.
However, cpack doesn't support arch generater, and it must be written at first hand or should write PKGBUILD file seperatly.
I suppose to,

1. write HanjpConfig.cmake.in and use CMakeConfigHelpers in top level CMakeLists.txt
2. write PKGBUILD file for arch linux.

[onting]

@OctopusET is handling second one.

[OctopusET]

#34

[onting]

#36 removes PKGBUILD file in our repo.
It it better to maintain source code and pakaging sepaeratly.