Fix warnings of -Weffc++

[jpnurmi]

There are lots of warnings when -Weffc++ is enabled: http://cutebin.fi/pipwgpbvw. The majority of warnings are due to members not being initialized in the initialization list.

Ref. znc/znc#270

[jpnurmi]

C++11 delegate constructor would make it easy to get rid of Init(), but is Csocket willing to depend on C++11 yet? If yes, I can prepare a patch.

[jimloco]

Csocket works fine with c++11, but given that it is a library that is used by multiple projects it needs to be able to work without c++11. Making Csocket compliant with -Weffc++ is a nice goal to have and is a reasonable request, but it is definitely low on my list of priorities. However, as time permits I'll address these issues.

Aside from the initialization lists, there are a couple of classes that need copy ctors and assignment operators, and CSocketManager would need to wrap vector<> as opposed to deriving from it. All of which are trivial fixes and just become busy work.