barrel_switcher_init small change

made delays be implemented as behavioural HDL so that compiler
can combine them with others and slightly reduce logic use.
reorder change

fanout into counter of sync_delay block and brams reduced by duplicating
delay from en port.
bus_maddsub fanout improvement

en duplication before addition layer changed from having latency of 1 to
mult_latency so that there is more latency to spread duplication across.
bus_replicate improvement

Duplication is accomplished using a tree fanout structure to
reduce fanout at every stage.
bus_dual_port_ram small fix
bus_single_port_ram bug fix

values saved in UserData of brams not being set properly
parameter added to fft_unscrambler

coeffs_bit_limit parameter added and logic added to decide whether
to implement map lookup using bram/s beyond this limit
fft_stage_n_init fanout improvement

register duplicated to reduce fanout
bi_real_unscr_4x_init timing improvement

if using bram for map, use bram_latency specified, not 1, and use 1
when using Distributed RAM to improve timing
fft_biplex_real_4x reorder map

Logic added to force implementation reorder map in bram in bi_real_unscr_4x
fft timing improvements

tweaking or various parameters
pfb_fir_generic timing improvements