Merging r275898:

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r275898 | hans | 2016-07-18 13:06:27 -0700 (Mon, 18 Jul 2016) | 8 lines

Revert r273099 "If the revision number starts with r, drop it. It will get added back"

This doesn't seem to work with Bash:

$ /work/llvm/utils/release/merge.sh --proj llvm --rev r275870
/work/llvm/utils/release/merge.sh: line 34: ${$1#r}: bad substitution

I get the same error with and without a leading 'r'.
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llvm-svn: 275900