Bower is unreliable, and we have to clear out the whole thing
in autogen.sh. Now that we're using webpack for bundling, we can
just bundle from nodejs modules instead.
This should solve bot problems that timeout when updating the modules
as well as allow automatically updating dependencies.
After this commit developers need to clear out their build and
run autogen.sh again from scratch.
$ git clean -fdx
$ mkdir build
$ cd build
$ ../autogen.sh --prefix=/usr
$ make -j8 all
Closes#6814
