fix bz5472979 server resources in build

[isao]

server affinity resources do not need to be uri-
addressable. With this change store.getAllUrls()
will no longer include foo.server.js resources,
and hence be omitted from mojito build

[isao]

thanks @drewfish for the fast diagnosis and remedy.

smoke test:

build html5app before this PR

% tree ../aaa-build-hybrid/ | grep server
│   │   │   ├── carrier.server.js
│   │   │   ├── cookie.server.js
│   │   │   ├── deploy.server.js
│   │   │   ├── device.server.js
│   │   │   ├── http.server.js
│   │       ├── hb.server.js
│   │       └── mu.server.js
│       ├── perf.server.js
│   ├── controller.server.js
│   │   └── foo.server.js
%

after:

% tree ../aaa-build-hybrid/ | grep server
%

[drewfish]

+1