experimental: moving packetizer definition inside internal header
build: removing 'experimental' from master branch

  * rather than enabling 'experimetal' build, moving to external branch
  * greatly simplifies build process
  * the main development is already in branches anyway
benchmark: using different task for estimating clock speed

  * smart compilers will realize that the loop doesn't do anything
  * this results in the loop not being run
  * new method is to generate semi-nondeterministic result and print it
  * still needs calibration for different machine types
build: separating 'AC_CHECK_LIB' to independent lines

  * modern compilers (e.g. LLVM and clang) are much more strict
  * running 'configure' would cause failures
  * trying to check all symbols within a single library failed
  * generated 'redefinition of foo as different kind of symbol' errors
  * configure was generating lines like this:

    char malloc, realloc, free, memset, memmove ();

  * compiler didn't like this
  * forcing configure to check each symbol separately fixes this
Merge branch 'master' of liquidsdr.org/liquid-dsp
build: removing internal compiler specification list
equalization: splitting complex compound statements for clang/llvm
filter: splitting complex compound statements for clang/llvm
matrix: splitting complex compound statements for clang/llvm
sandbox/fft: splitting complex compound statements for clang/llvm
sandbox: duplicating packetizer structure inside sandbox source
build: replacing AC_CHECK_LIB with favorable AC_CHECK_FUNC
build: purging experimental files; build now lives in separate branch
Merge branch 'master' of liquidsdr/master