hgmerge: various cleanups
Details:
- put temporary file names into variables
- make all temporary file names end with random part
- cleanup FileMerge handling
- do not use hardlinks in FileMerge change test (breaks on FAT)
- try harder to keep file mtime unchanged in case of failed merge
<div>
<a class="title" href="?cmd=changeset;node=#node#;style=gitweb"><span class="age">#date|age# ago</span>#desc|firstline|escape#</a>
</div>
<div class="title_text">
<div class="log_link">
<a href="?cmd=changeset;node=#node#;style=gitweb">changeset</a><br/>
</div>
<i>#author|obfuscate# [#date|rfc822date#]</i><br/>
</div>
<div class="log_body">
#desc|escape|addbreaks#
<br/>
<br/>
</div>