gdalbuildvrt: add page (#4941)

pages/common/gdalbuildvrt.md

@@ -0,0 +1,20 @@
+# gdalbuildvrt
+
+> Build Virtual Datasets from a list of existing datasets.
+> More information: <https://gdal.org/programs/gdalbuildvrt.html>.
+
+- Make a virtual mosaic from all TIFF files contained in a directory:
+
+`gdalbuildvrt {{path/to/output.vrt}} {{path/to/input_directory/*.tif}}`
+
+- Make a virtual mosaic from files whose name is specified in a text file:
+
+`gdalbuildvrt -input_file_list {{path/to/list.txt}} {{path/to/output.vrt}}`
+
+- Make a RGB virtual mosaic from 3 single-band input files:
+
+`gdalbuildvrt -separate {{path/to/rgb.vrt}}  {{path/to/red.tif}] {{path/to/green.tif}} {{path/to/blue.tif}}`
+
+- Make a virtual mosaic with blue background colour (RGB: 0 0 255):
+
+`gdalbuildvrt -hidenodata -vrtnodata "{{0 0 255}}" {{path/to/output.vrt}} {{path/to/input_directory/*.tif}}`