moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

moved crates in lib/ to src/, renamed crates, modified some files' text (#660)

cranelift/codegen/meta-python/isa/arm64/settings.py

@@ -0,0 +1,11 @@
+"""
+ARM64 settings.
+"""
+from __future__ import absolute_import
+from cdsl.settings import SettingGroup
+import base.settings as shared
+from .defs import ISA
+
+ISA.settings = SettingGroup('arm64', parent=shared.group)
+
+ISA.settings.close(globals())