COMMON: Return NULL in wrapCompressedReadStream for compressed streams when ZLIB is disabled.
CONFIGURE: Never enable release_build by default.

This changes the default for Caanoo, GP2x, GP2xWiz, OpenPandora and PS2.
For those now we only disable debug symbols and enable optimizations by
default.
Merge pull request #303 from lordhoto/wrap-compressed

Return NULL in wrapCompressedReadStream for compressed streams when ZLIB is disabled.
WINTERMUTE: Add override-tags to most of the overriden functions in base/gfx.
WINTERMUTE: Replace a few NULLs with nullptr.
GRAPHICS: Modify the JFIF version warning

v1.02 images should only differ with the thumbnail from v1.01, and should be handled correctly by our decoder.
WINTERMUTE: Replace all NULLs with nullptr.
COMMON: Make BufferedSeekableReadStream use the buffer with SEEK_SET and SEEK_END
TESTS: Add failing test for repeated seeks in BufferedSeekableReadStream
JANITORIAL: Enforce "} // End of namespace" with a single space after }.
JANITORIAL: Use "End of anonymous namespace" as comment for anonymous namespaces.
SCUMM: Work around bug #3602239 ("Mac Loom crashes using opening...")

Skip music resources that don't have the "so" (song?) tag. It is
better than asserting, now that it turns out that they do exist.
SCUMM: Update handling of non so resources in Loom Mac.

This changes the warning to a debug and also updates the comment a bit.
Thanks to eriktorbjorn for checking Loom Mac in an emulator.
GUI: Allow user to display hidden files in the browser dialog.

This implements feature request #3600774 "File browser: show hidden files".
WINTERMUTE: Move Resources out of binary and into wintermute.zip
BUILD: Add wintermute.zip to resource file for Windows builds.
Merge pull request #306 from lordhoto/filechooser-hidden

GUI: Allow user to display hidden files in the browser dialog.
COMMON: Fix successive seeks in BufferedSeekableReadStream.

This fixes the failing test case added in
da8eeb9dbed2102764b3ca0697d6882bae0402cc.

Thanks to wjp for his input on this.
Merge pull request #305 from giucam/bufferedseekable

Make BufferedSeekableReadStream use the buffer with SEEK_SET and SEEK_END
SCI: Use correct priority selector in SoundCmd

It was using 'pri' instead of 'priority', apparently due to a
selector number->name translation error from 544daa5c31.

Thanks to waltervn for spotting this.