dring: Rename to jamid. Likewise for ringcli.

This change renames the dring binary to jamid on GNU/Linux, and from
ringcli to jamid on the other Windows/Mac platforms.

* .gitignore: Ignore bin/jamid instead of bin/dring.
* bin/Makefile.am (bin_PROGRAMS)[HAVE_WIN32]: Replace ringcli by
jamid.
(ringcli_SOURCES)[HAVE_WIN32]: Rename to jamid_SOURCES.
(ringcli_CXXFLAGS)[HAVE_WIN32]: Rename to jamid_CXXFLAGS.
(ringcli_LDADD)[HAVE_WIN32]: Rename to jamid_LDADD.
[HAVE_OXS]: Likewise for each of the above 4 variables.
(bin_PROGRAMS): Replace dring by jamid.
(dring_SOURCES, dring_CXXFLAGS, dring_LDADD): Replace the 'dring'
Automake variables prefix by 'jamid'.
* bin/dbus/cx.ring.Ring.service.in (Exec)<dring>: Rename to 'jamid'.

Change-Id: I3f41846a38e74e2f3c6f687a46e1a208f0083ca2