posix.mak: add freebsd/osx compatibility

`-u` is not recognized `cp` flag on freebsd/osx.
Merge pull request #103 from humdedum/posix.mak

posix.mak: add freebsd/osx compatibility
Update DustMite

Commits:
* 1f0a0cd dustmite: Fix deprecated use of canFind
* 1035b15 dustmite: Improve progress indicator accuracy
* 556a9ab dsplit: Avoid stack overflow with very long lists
* 6b8f49c Avoid std.string.startsWith, which does pointless UTF-8 decoding
* 8eb5282 dsplit: Don't parse DDoc files as D source
* 403ef2f dsplit: Fix possible range violations in skipSymbol
Merge pull request #105 from CyberShadow/dustmite-20140107

Update DustMite
Add --nocache option to force a bugzilla query.
Merge pull request #106 from AndrejMitrovic/AddForce

Add --nocache option to force a bugzilla query.
rdmd: Clean up the old executable file before the build starts

The old code attempted to delete the final executable if the build
failed, disregarding potential failure due to it being in use.

Now we safely ensure that the final executable doesn't exist before
we even start building.
Merge pull request #107 from CyberShadow/rdmd-20140109

rdmd: Clean up the right executable file if the build fails
rdmd: Add etc to list of ignored packages

This fixes "The module 'etc.c.curl' is already defined in (program)".
Merge pull request #108 from CyberShadow/rdmd-20140118

rdmd: Add etc to list of ignored packages
fix update function

- need to use expanding string for projects
Merge pull request #109 from MartinNowak/fixUpdate

fix update function
rdmd: Clean up the temporary executable file if the build fails

OPTLINK may leave behind a broken executable, although the build failed.
Depending on user options, this .tmp file may reside outside the
rdmd work directory, so clean it up if it is created.
Merge pull request #110 from CyberShadow/rdmd-20140127

rdmd: Clean up the temporary executable file if the build fails
rdmd: Use execv on supported systems
Merge pull request #112 from CyberShadow/rdmd-20140201

rdmd: Use execv on supported systems
rdmd: Fix --dry-run
rdmd_test: Add test for issue 11983
Merge pull request #113 from CyberShadow/rdmd-20140202

rdmd: Fix `--dry-run`, add test for issue 11983
Fix #12149: ".exe" not auto-added with -of on windows.