Remove an unnecessary field from generated makefiles
Enable threading when building for most platforms

Don't enable threading globally since the MSVC/ARM build target
(neither windows phone nor windows rt) doesn't support the normal
windows threading functions.
Remove spaces from the argument to LINK_LIB

In make on some platforms, this ended up as passing -l <lib>
with a space inbetween. This wasn't an error, but wasn't what
was intended either.
Remove the legacy makefile based build system

The new one is much more flexible. The old one is unmaintained.
Use 'inline' instead of 'inline_t' in the processing lib

Just use the standard inline keyword with sufficient backwards
compatibility defines, similar to how it is done in the main decoder
and encoder libraries.
Consistently use inline instead of __inline
Unify the definition of WELS_THREAD_ERROR_CODE between libraries

This simplifies the code base, reduces the risk for mixups and
gets rid of the use of a local nonstandard typedef.
Use int32_t instead of long_t in WELS_SIGN/WELS_ABS in the processing lib

This makes them match the same macros in the main decoder/encoder
libraries. long_t (which is typedeffed to long) actually is 64
bit on 64 bit unix platforms, which might not be what was
intended.
Remove the now unused long_t typedef
Make the bool_t typedef in the processing lib match the others

There is no specific reason to use int32_t for this type.
Unify the declaration of int8_t within the processing lib with the rest

int8_t in general should to be defined as signed char, since there
are actual envrionments where a plain 'char' is unsigned.

This also reduces the differences between the typedef headers of
the different sub-libraries.
Readd a removed include

This fixes builds without NO_DYNAMIC_VP (such as with the MSVC
project files), the include was removed in d809b7e9.
Remove the FOPEN macro, use WelsFopen instead

This avoids ifdefs at each place the macro is used.
Make WelsVsprintf use vsnprintf, to check the buffer size

Otherwise builds on platforms other than MSVC might be
insecure.

Use vsnprintf_s with the _TRUNCATE flag instead of vsprintf_s
when using MSVC - this truncates the buffer instead of aborting
the whole process in case it's too small.
Rename WelsVsprintf to WelsVsnprintf, to indicate that it actually checks the length
Use vsnprintf in the old MSVC version of WelsSnprintf as well
Make sure the buffer always is null terminated in the *snprintf calls for old MSVC

These functions leave the buffer unterminated in case it was too
small.
Make sure the buffer is null terminated after strftime

If the buffer is too small, there's no guarantee that it is
null terminated. The docs (on both unix and MSVC) say explicitly
that the function returns 0 and the buffer contents are
indeterminate in this case.
Move the measure_time.h header to the common library

Both encoder and decoder versions were functionally equivalent,
but I picked the decoder version (but added the static inline
keywords to it) since the encoder one was quite messy with a lot
of commented out code.
Merge the ls_defines.h headers into the common sub-library