Allow using GObject.signal_* functions in place of Object methods

GObject.Object.connect() and friends might be unavailable because
shadowed by another method in the prototype chain (such as
g_socket_connect()).
In that case, it is nice to use the C equivalents, which are
GObject.signal_connect(), GObject.signal_handler_disconnect() and
GObject.signal_emit_by_name().

(Philip Chimento: Rebased, ported test to Jasmine, and fixed coding
style.)

Closes #65.
4 jobs for wip/gcampax/65-gobject-signal in 23 minutes and 51 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
passed #5748
fedora_clang

00:12:24

68.8%
passed #5749
fedora_cppcheck

00:00:28

passed #5747
fedora_gcc

00:10:59

 
  Failure
skipped #5750
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