Merge pull request #329 from diizy/stable-0.4

AudioFileProcessor knob fix
Merge pull request #330 from diizy/stable-0.4

New icon and splash images
LadspaEffect: fixed default value if hints are sample rate dependent

When hints are sample rate dependent we also need to scale default
value accordingly as well.

Closes #334.
DynamicsProcessor: fixed Win32 build issue

For some reason isnanf() is not defined when building with recent MinGW64
toolchain, therefore define it manually if neccessary.
Removed libsamplerate from source tree

Drop another 3rdparty component and rely on system libraries instead.
Travis: remove duplicate libsamplerate0-dev dependency
NSIS/FileAssociation: do not write DefaultIcon registry key

Setting the DefaultIcon registry key uses LMMS' logo instead of a file
icon with the logo inside.

Thanks to Tres Finocchiaro for spotting the issue.
RemotePlugin: always use installation directory as working directory

On Windows the working directory is not set to the installation directory
when launching LMMS by opening an associated project file. Because of this
the RemotePlugin programs can't be launched as the required DLL files are
missing.

Closes #351.
Pattern: removed freeze functionality

Since addition of automation, controllers etc. the freeze functionality
has been rather broken and thus adds no value anymore. In order to not
confuse users with broken functionality, remove it at all.

Closes #345.
Second release candidate for 1.0.0

Bumped version number to 0.9.90 in CMakeLists.txt, README and lmms.rc.in.
Allow piano roll playing while playing, fixes #21