Elementary cygwin support

This patch adds elementary cygwin support (i.e. xiki process runs and xiki command can talk to it and present responses to terminal).

The general gist of the changes are as follows:

FIFO changed to TCPServer / TCPSocket - FIFOs were causing errors during flush on cygwin
"running" check changed to use Daemon PID file checks as ps output does not contain script names on cygwin (plus it's a flakey way to check)
xiki_process.rb refactored to allow inclusion without slowing down
As a result of the above, xiki_process bin script created to execute the server
Bug fix in lib/xiki/menu.rb that caused = vs == warning
Hack for a bug in ruby_parser 2.3.1 to prevent redeclared constant errors

trogdoro / xiki