Remove spirv_new binaries and add Python script to generate them (#902)

* Remove binaries for spirv_new (#21)

Avoid storing binaries in version control, as it is generally not well
suited to this.  Instead, in a followup commit we will add a script to
regenerate the .spv files from their sources.

Signed-off-by: Stuart Brady <stuart.brady@arm.com>

* Add Python script to assemble spirv_new binaries (#21)

This also changes the ext_cl_khr_spirv_no_integer_wrap_decoration assembly
source so that the SPIR-V version is listed as 1.0, to ensure that the
output of spirv-dis exactly matches the assembly.

Signed-off-by: Stuart Brady <stuart.brady@arm.com>