Copy: when copied source is a symlink, follow it
1) hg cp symlink copy -> copy is a symlink.
2) cp symlink copy; hg cp -A symlink copy -> copy is a regular file.
In the second case we have to follow the symlink to its target
to find out whether we have to unexpand keywords in the copy.
Add test covering the case where the copied link's target is ignored
by keyword but has content which would match the regex for expanded
keywords to check whether we indeed leave the destination alone.
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1fe48bf82d056f1ece05baccab888357c10c5ab8 r0.1
2e930f84224222ad6514a3c5dc6e00350e199e92 very_cvs
99dc49c5bcfba9d5b412c5fa6d0bf3ba20d68df1 hgkw_standalone_setup
15e8cd7f5295728b089fc8ba236c0f079572fb1d nohook
0c8b7e5c25a6b9a0d2782eaa3748eb546f5a254f archive
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0000000000000000000000000000000000000000 nohook
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