Add compiled assets to the gitignore (#267)

* Ignore compiled js files in git

* Adjust gitignore values

* Adjust to shell glob instead of regex

* Remove compiled files to init the gitignore rules

* Remove compiled assets from git tracking

* remove my-cool-element from test file

* include themes in gitignore, and don't ignore tooling files

* remove the ignored files

* re-add the root copy of pfe-icons.svg

* move pfe-avatar story file into src

* don't copy src/story files into element dirs

* move story files into demo dir

* clean up unnecessary *.story.js omission

Author: castastrophe

.gitignore

@@ -2,6 +2,21 @@
 node_modules
 tmp
 
+# ignore js, map, and css in element dirs
+elements/*/*.js
+elements/*/*.map
+elements/*/*.css
+# but don't ignore tooling files
+!elements/*/gulpfile.js
+!elements/*/rollup.config.js
+
+# and same for themes
+themes/*/*.js
+themes/*/*.map
+themes/*/*.css
+!themes/*/gulpfile.js
+!themes/*/rollup.config.js
+
 # Compiled index
 doc/index.html