AnyImageImporter: recognize PGM and PPM formats.

Newly supported by StbImageImporter.

src/MagnumPlugins/AnyImageImporter/AnyImageImporter.cpp

@@ -60,10 +60,14 @@ void AnyImageImporter::doOpenFile(const std::string& filename) {
         plugin = "HdrImporter";
     else if(Utility::String::endsWith(filename, ".jpg") || Utility::String::endsWith(filename, ".jpeg"))
         plugin = "JpegImporter";
+    else if(Utility::String::endsWith(filename, ".pgm"))
+        plugin = "PgmImporter";
     else if(Utility::String::endsWith(filename, ".pic"))
         plugin = "PicImporter";
     else if(Utility::String::endsWith(filename, ".png"))
         plugin = "PngImporter";
+    else if(Utility::String::endsWith(filename, ".ppm"))
+        plugin = "PpmImporter";
     else if(Utility::String::endsWith(filename, ".psd"))
         plugin = "PsdImporter";
     else if(Utility::String::endsWith(filename, ".tga"))

src/MagnumPlugins/AnyImageImporter/AnyImageImporter.h

@@ -54,8 +54,10 @@ tries to open the file with it. Supported formats:
 -   JPEG (`*.jpg`, `*.jpeg`), loaded with @ref JpegImporter or any other plugin
     that provides it
 -   PIC (`*.pic`), loaded with any plugin that provides `PicImporter`
+-   PGM (`*.pgm`), loaded with any plugin that provides `PgmImporter`
 -   PNG (`*.png`), loaded with @ref PngImporter or any other plugin that
     provides it
+-   PPM (`*.ppm`), loaded with any plugin that provides `PpmImporter`
 -   PSD (`*.psd`), loaded with any plugin that provides `PsdImporter`
 -   TGA (`*.tga`), loaded with @ref TgaImporter or any other plugin that
     provides it