specials/Memory: allow for more flexibility in memory port signals
utils/misc: add gcd_multiple function to compute GCD or any number of integers
fhdl/simplify: add FullMemoryWE decorator that splits memories to remove partial WEs
add support for Verilog include paths
fhdl/simplify/FullMemoryWE: fix WE slice for multi-port mems
migen/fhdl/tools: speed up group_by_targets (halves the mixxeo runtime)