Rename mmcv package name

[zhouzaida]

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Motivation

Since mmcv v2.0.0rc1, we rename the package name mmcv to mmcv-lite and mmcv-full to mmcv for two reasons:

• Most users use mmcv-full, but it is inconsistent with the name of the repo, which will lead to confusion
• Users include mmcv-full in the requirements, but the mmcv repo cannot show the downstream libraries that use mmcv

Modification

Please briefly describe what modification is made in this PR.

BC-breaking (Optional)

Before this PR

• install mmcv with ops

pip install mmcv-full -f xxxx
# or
pip install mmcv-full

• install mmcv without ops

pip install mmcv

After this PR (mmcv v2.0.0rc1)

• install mmcv with ops

pip install 'mmcv>=2.0.0rc1' -f xxxx
# or
pip install 'mmcv>=2.0.0rc1'

• install mmcv without ops

pip install mmcv-lite

Another BC-breaking is to change MMCV_WITH_OPS from 0 to 1 by default. That means if users do not set MMCV_WITH_OPS=0, the program will install mmcv with ops.

Use cases (Optional)

If this PR introduces a new feature, it is better to list some use cases here, and update the documentation.

Checklist

Before PR:

• I have read and followed the workflow indicated in the CONTRIBUTING.md to create this PR.
• Pre-commit or linting tools indicated in CONTRIBUTING.md are used to fix the potential lint issues.
• Bug fixes are covered by unit tests, the case that causes the bug should be added in the unit tests.
• New functionalities are covered by complete unit tests. If not, please add more unit test to ensure the correctness.
• The documentation has been modified accordingly, including docstring or example tutorials.

After PR:

• If the modification has potential influence on downstream or other related projects, this PR should be tested with some of those projects, like MMDet or MMCls.
• CLA has been signed and all committers have signed the CLA in this PR.