Add CMake support

Clean up file structure.
Update build scripts.

base/mellow.conf

@@ -0,0 +1,27 @@
+[Endpoint]
+DIRECT, builtin, freedom, domainStrategy=UseIP
+REJECT, builtin, blackhole
+Dns-Out, builtin, dns
+
+[Routing]
+domainStrategy = IPIfNonMatch
+
+[Dns]
+hijack = Dns-Out
+clientIp = 114.114.114.114
+
+[DnsServer]
+localhost
+223.5.5.5
+8.8.8.8, 53, Remote
+8.8.4.4
+
+[DnsRule]
+DOMAIN-KEYWORD, geosite:geolocation-!cn, Remote
+DOMAIN-SUFFIX, google.com, Remote
+
+[DnsHost]
+doubleclick.net = 127.0.0.1
+
+[Log]
+loglevel = warning