Bump the trunk version to 10.0.0svn

and clear the release notes.

llvm-svn: 366427
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 8f5b44aead89a56c6fbf85ccfda03ae1e82ac431
diff --git a/docs/conf.py b/docs/conf.py
index e88b2d3..414f1bc 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -47,9 +47,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '9.0'
+version = '10.0'
 # The full version, including alpha/beta/rc tags.
-release = '9.0'
+release = '10.0'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.