Add webp image format support (load and save).

Fix bug introduced in the last commit for UIDataBind initialization.
Change gmake2 in favor of gmake when using premake5 since it has been depreated in premake5-beta6 (hopefully I did not miss anything).

.ecode/project_build.json

@@ -119,7 +119,7 @@
   "ecode-windows": {
     "build": [
       {
-        "args": "--windows-mingw-build gmake2",
+        "args": "--windows-mingw-build gmake",
         "command": "premake5.exe",
         "working_dir": ""
       },
@@ -288,6 +288,12 @@
         "command": "${project_root}/bin/eepp-7guis-timer-debug",
         "name": "eepp-7guis-timer-debug",
         "working_dir": "${project_root}/bin"
+      },
+      {
+        "args": "",
+        "command": "${project_root}/bin/eeiv-debug",
+        "name": "eeiv-debug",
+        "working_dir": "${project_root}/bin"
       }
     ],
     "var": {
@@ -511,7 +517,7 @@
   "eepp-windows": {
     "build": [
       {
-        "args": "--windows-mingw-build gmake2",
+        "args": "--windows-mingw-build gmake",
         "command": "premake5.exe",
         "working_dir": ""
       },