Log message:
Add build dependency on pkgconfig.

While here, rearrange paragraphs so that buildlink3.mk files are
included before overriding targets.

Log message:
Libtool fix for PR pkg/26633, and other issues.  Update libtool to 1.5.10
in the process.  (More information on tech-pkg.)

Bump PKGREVISION and BUILDLINK_DEPENDS of all packages using libtool and
installing .la files.

Bump PKGREVISION (only) of all packages depending directly on the above
via a buildlink3 include.

Log message:
import gsmc-1.1

gsmc is a GTK application that allow to do all the calculation
usually done on a Smith Chart.  It permits to make calculation
for network composed by resistor, capacitor, inductance, and
transmission line (also as stub).  Network topology is
limited to series, parallel and as trasmissive
for trasmission line. No series connection are allowed in parallel
branch, neither parallel connection in series branch.
Trasmission line can be placed as quadrupole or as a parallel or
series stub, either opened or shorted at the other end.

Calculation procedure starts with setting the initial impedance to be
matched, next network elements are added and tuned to obtain the
desidered impedance value.

The network so obtained can be saved in spice format for other analysis;
current work can be saved for succesive retrieve.

The initial (start) impedance is thought as "the load" so when
adding a trasmission line placed as a quadrupole rotation is
clockwise, going "toward generator"; generator is placed after the
last network element, as can be seen from spice output.