Added ability to set connection timeout values.

[jim0020]

Can set a connection timeout value, in seconds (NSTimeInterval), as a default for all FSNConnection instances, and individually.

[mattchukabam]

That looks good to me. @gwk Good enough to merge?

[gwk]

this looks fine to me. style points:

• method braces are inconsistent with the rest of the project.
• i would not use double-underscore prefix for a static variable, because i think of those as being reserved for macro temps and compiler internals.
  other than those minor details it looks great. however i have not actually tested/observed the custom timeout behavior.
  thanks jim!

[dyorgio]

Come on guys :), merge timeout support to HEAD.