OZP-61: Migrate RPC API.

1. Replacing maven web-minifier plugin with maven minify plugin to fix Travis build issue where the order of the minified files is different than Jenkins' order, which couldn't be controlled by web-minifier.
2. Removed separate html js bundle files, which are now defined in the corresponding poms for the maven minify plugin.
OZP-61: Migrate RPC API.

1. Clean up from original RPC commit.
2. Fixed intermittent RPC bug where Constants object was null due to not being defined properly in a require js enabled environment.
3. Removed unnecessary global variables in require js environment.
Merge branch 'master' into feature/establish-keyboard-nav