tpaw_account_settings_parameter_is_valid: use tp_vardict_has_key

Based on a patch by Guillaume Desmottes.
Fix underlinking

If we don't link the .la file to the libraries it depends on,
every project that embeds this submodule will have to link to
those libraries itself.
TpawConnectionManagers: use TpClientFactory instead of TpDBusDaemon

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=76828
Remove INSTALL from git

It's an unmodified Automake version, and autogen.sh overwrites it
with the current Automake's version (which might be different).