Render rollYourOwn template of the themeroller page on frontend

rollYourOwn contents exchanged between server and client are no longer needed, it's all rendered on client based on theme vars.

Traffic changes:

- first page load (eg. clicking themeRoller tab): Increased by 13% (344.7KB now vs. 305.2KB prev). JS code traffic only; But, note JS is not yet minified, and note JS is static, further loads wont fetch it all again;
- first page load with a theme in querystring (eg. via downloadBuilder): Reduced by 7% (447KB now vs. 479.6KB prev) [1]
- Per quest load picking a themeGallery: reduced by 100% (0KB vs. 40.5KB) per transaction; [2]

1: Now: 102.3KB (HTML), 344.7KB (JS), Prev: 133.9KB + 40.5KB (HTML), 305.2KB (JS).
2: Now: 0KB (HTML), Prev: 40.5KB (HTML).

Notes: (a) Templates are precompiled on server and served via a .JS file app/resources/template/themeroller.js, which is static, so further requests of this same file by the same client tends to be skipped. (b) JSes are not yet minified, this sizes tend to reduce significantly.