docs: add catalogue to Process Manage

See merge request !21

doc: add catalogue to system call.md

See merge request !20

Vesion: 0.2

docs: design document for system call.

See merge request !19

Version: 0.1

docs: add docs for kernel startup

See merge request !18

docs: design document for process management

See merge request !17

updata README.md

See merge request !16

docs: update README.md, add information, progress and update build guide

See merge request !15

Version: 0.1

feat:add mm.md

See merge request !14

feat & docs: Improve the kernel and doc comments

See merge request !13

feat: Add support and improve file handling for the kernel file system

See merge request !12