This pull request primarily removes submodule management targets from
the `Makefile` and makes minor updates to the project documentation in
both English and Chinese. The most important changes are grouped below.
Makefile cleanup:
* Removed the `subup` and `subsync` targets from the `Makefile`,
eliminating commands related to updating and committing submodules.
Documentation updates:
* Updated the logo alt text in both `README.MD` and `README.zh_CN.MD`
from "goframe gf logo" to "goframe logo" for clarity.
[[1]](diffhunk://#diff-01e6d9ffed056a02cae8d8a0ec5d476a64d017bf85c0d5a94bb23ca21f33f5aaL4-R4)
[[2]](diffhunk://#diff-c93759cb9a9500f20e551c741eb167fc72825fd638d36121357feb8253ce6ac1L4-R4)
* Revised a description in `README.zh_CN.MD` to clarify the framework's
purpose, changing “一个强大的框架” to “一款强大的框架”.
* Simplified the license description in `README.zh_CN.MD` to state
"100%开源和免费".
