[Docs] Refactor the structure of documentation (#1580)

* [Docs] Refactor the structure of documentation

* [Docs] Refactor the structure of documentation

* fix symlink

* fix link

* fix typo

* polish docstring

* fix docstring

docs/api.rst → docs/en/api.rst

@@ -38,6 +38,11 @@ runner
 .. automodule:: mmcv.runner
     :members:
 
+engine
+------
+.. automodule:: mmcv.engine
+    :members:
+
 ops
 ------
 .. automodule:: mmcv.ops

docs/en/community/contributing.md

+../../../CONTRIBUTING.md
\ No newline at end of file

docs/conf.py → docs/en/conf.py

@@ -17,9 +17,9 @@ import sys
 import pytorch_sphinx_theme
 from sphinx.builders.html import StandaloneHTMLBuilder
 
-sys.path.insert(0, os.path.abspath('..'))
+sys.path.insert(0, os.path.abspath('../..'))
 
-version_file = '../mmcv/version.py'
+version_file = '../../mmcv/version.py'
 with open(version_file, 'r') as f:
     exec(compile(f.read(), version_file, 'exec'))
 __version__ = locals()['__version__']

docs/get_started/installation.md → docs/en/get_started/installation.md

@@ -138,7 +138,7 @@ For more details, please refer the the following tables.
 </table>
 
 ```{note}
-The pre-built packages provided above do not include all versions of mmcv-full, you can click on the corresponding links to see the supported versions. For example, if you click [cu102-torch1.8.0](https://download.openmmlab.com/mmcv/dist/cu102/torch1.8.0/index.html), you can see that `cu102-torch1.8.0` only provides 1.3.0 and above versions of mmcv-full. In addition, We no longer provide `mmcv-full` pre-built packages compiled with `PyTorch 1.3 & 1.4` since v1.3.17. You can find previous versions that compiled with PyTorch 1.3 & 1.4 [here](./docs/get_started/previous_versions.md). The compatibility is still ensured in our CI, but we will discard the support of PyTorch 1.3 & 1.4 next year.
+The pre-built packages provided above do not include all versions of mmcv-full, you can click on the corresponding links to see the supported versions. For example, if you click [cu102-torch1.8.0](https://download.openmmlab.com/mmcv/dist/cu102/torch1.8.0/index.html), you can see that `cu102-torch1.8.0` only provides 1.3.0 and above versions of mmcv-full. In addition, We no longer provide `mmcv-full` pre-built packages compiled with `PyTorch 1.3 & 1.4` since v1.3.17. You can find previous versions that compiled with PyTorch 1.3 & 1.4 [here](./previous_versions.md). The compatibility is still ensured in our CI, but we will discard the support of PyTorch 1.3 & 1.4 next year.
 ```
 
 Another way is to compile locally by running