Syntax checking too restrict for set_engine_par

[andreasOL16]

According to

http://vi-control.net/community/threads/additions-to-the-sublimeksp-compiler.53496/page-2#post-3966055

the plugin disallows assignment of a return value of set_engine_par. Normally that function does not return a value. But for ENGINE_PAR_EFFECT_SUBTYPE as in e.g.

filter_load_id := set_engine_par(ENGINE_PAR_EFFECT_SUBTYPE,FILTER_TYPE_SV_LP4,-1,2,NI_BUS_OFFSET+1)

it does and the plugin rejects this with

Expected expression of integer type, got None

[andreasOL16]

This is already handled in "Concat arrays and lists of lists #19" under bug fixes