Introduce README.
Introduce README.

The new README includes the following elements:
 - Introduction
 - Feature list
 - Installation and usage
 - Multiple bullets

The following needs to be done (TODO):
 - License
 - Better feature list

Signed-off-by: f6cb034ae1bf314d2c0261a7a22e4684d1f74b57@gmail.com <f6cb034ae1bf314d2c0261a7a22e4684d1f74b57@gmail.com>

Gitub/BlocksKit,tattocau/BlocksKit,Herbert77/BlocksKit,HarrisLee/BlocksKit,hartbit/BlocksKit,yimouleng/BlocksKit,TomBin647/BlocksKit,Voxer/BlocksKit,AlexanderMazaletskiy/BlocksKit,stevenxiaoyang/BlocksKit,demonnico/BlocksKit,yaoxiaoyong/BlocksKit,dachaoisme/BlocksKit,coneman/BlocksKit,shenhzou654321/BlocksKit,pilot34/BlocksKit,zhaoguohui/BlocksKit,z8927623/BlocksKit,xinlehou/BlocksKit,ManagerOrganization/BlocksKit,hq804116393/BlocksKit,owers19856/BlocksKit,pomu0325/BlocksKit,zxq3220122/BlocksKit-1,aipeople/BlocksKit,anton-matosov/BlocksKit,zwaldowski/BlocksKit