Libedit deps fix

Configuration fix

Situation:

Currently there are three problems when configuring the sources:

1. When configuring with --with-libedit=/is/somewhere/else the header files location is not passed into appropriate translation units and the compilation fails on missing header file histedit.h.

2. Compilation fails with --disable-daemon and --enable-utilities because libedit is pulled by static dependencies of utilities but is not detected in the configuration because of disabled daemon.

3. Sources of knotc are compiled with daemon but the resulting binary is only built(linked) when utilities are also enabled, because utilisties provide necessary static libknotus.la.

Solution:

• Add missing $(libedit_CFLAGS) into src/Makefile.am on relevant places.
• Presence of libedit is checked when configuring with daemon or utilities.
• Changes in src/Makefile.am so that libknotus.la is built when HAVE_DAEMON or HAVE_UTILS. Utility knotc is compiled and built with knotd.