pkg-config: move to common (#8267)

pages/common/pkg-config.md

@@ -0,0 +1,16 @@
+# pkg-config
+
+> Provide the details of installed libraries for compiling applications.
+> More information: <https://www.freedesktop.org/wiki/Software/pkg-config/>.
+
+- Get the list of libraries and their dependencies:
+
+`pkg-config --libs {{library1 library2 ...}}`
+
+- Get the list of libraries, their dependencies, and proper cflags for gcc:
+
+`pkg-config --cflags --libs {{library1 library2 ...}}`
+
+- Compile your code with libgtk-3, libwebkit2gtk-4.0 and all their dependencies:
+
+`c++ example.cpp $(pkg-config --cflags --libs gtk+-3.0 webkit2gtk-4.0) -o example`