Symbolic execution PoC #1600

Job	Run time
Build Echidna on ubuntu-20.04	4m 15s
Build Echidna on macos-latest	2m 56s
Build Echidna on windows-latest	8m 22s
Test with solc 0.4.25 on ubuntu-latest	3m 59s
Test with solc 0.5.7 on ubuntu-latest	4m 29s
Test with solc 0.6.12 on ubuntu-latest	6m 29s
Test with solc 0.7.5 on ubuntu-latest	6m 10s
Test with solc 0.4.25 on windows-latest	6m 42s
Test with solc 0.5.7 on windows-latest	7m 20s
Test with solc 0.6.12 on windows-latest	5m 19s
Test with solc 0.7.5 on windows-latest	9m 48s
	1h 5m 49s

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