Avoid using global installations of tsc, bower, gulp

[aldonline]

When running dev_setup.sh, the program halted a couple of times when it failed to find globally installed versions of gulp, tsc and bower.
While this is a common practice, it can lead to all sorts of version issues (specially tsc!).
My suggestion is to use locally installed versions when possible:
./node_modules/typescript/bin/tsc.