Copy ag-grid CSS to the resources folder.

The directory `resources/css/ag-grid-community` is created on
`npm run build`, and its contents are gitignored. On `npm run build
clean`, the directory and its contents are deleted.

.gitignore

@@ -6,6 +6,7 @@ resources/scripts/xqlint.min.js
 resources/scripts/ace
 resources/scripts/eXide.min.*
 resources/scripts/jquery/jquery.plugins.min.*
+resources/css/ag-grid-community/
 
 tools/r.js
 

scripts/build.js

@@ -125,6 +125,7 @@ async function clean() {
         'resources/scripts/jquery/jquery.plugins.min.js', 
         'resources/scripts/xqlint.min.js', 
         'resources/scripts/ace/**',
+        'resources/css/ag-grid-community/**',
         'index.html',
         'expath-pkg.xml'
     ], { allowEmpty: true, silent: false });
@@ -180,6 +181,8 @@ function replace(path, outPath, data) {
     }
 
     await mfs.copy('./support/ace/build/src-min/**', './resources/scripts/ace');
+    await mfs.copy('./node_modules/@ag-grid-community/core/LICENSE.txt', './resources/css/ag-grid-community');
+    await mfs.copy('./node_modules/@ag-grid-community/core/dist/styles/*.css', './resources/css/ag-grid-community');
 
     replace('expath-pkg.xml.tmpl', 'expath-pkg.xml', { version });
     replace("index.html.tmpl", "index.html", { version });