Add Bower-specific commands to building all folder's contents / entire project

[JordanMartinez]

Currently, each folder has a copy-and-pasteable bash command that builds the folder's contents or runs the tests, etc.

However, this only uses psc-package to do so. It might be worthwhile to include commands for both Bower and psc-package so that learners are not restricted to either dependency manager in their learning process.

For context, see thomashoneyman/purescript-halogen-realworld#13

[JordanMartinez]

This would also contribute towards #137

[JordanMartinez]

I keep going back and forth as to whether to do this.

Reasons why I want to do this:

• partly for completion: the reader can then use whatever build tool they desire and future library authors have a workflow for publishing libraries
• partly for ease of learning: Bower requires learning less to use, can be setup/installed easily, and only really sucks when a compiler release with breaking changes is made or when a library hasn't been updated for the release used in this repo.

Reasons why I don't want to do this:

• unneeded work: a reader can already use/compile this repo's code, so why do the extra work?
• future maintenance problems: when a new breaking change is released in the compiler, it'll be a pain to update everything Bower-related whereas psc-package makes this trivial. In a recent conversation on FP Slack, others agreed that psc-package is more ideal than Bower for new learners when all libraries used in lessons are known beforehand and exist in the package set.
• forward-thinking: spago keeps getting more mature day-by-day. How much longer until we no longer need to use Bower? Even so, a package-set's "all or nothing" approach only works as long as all libraries are compatible. When a new compiler release is made, no one can benefit from it using psc-package until all libraries in the package set has been fully updated.

[JordanMartinez]

A lot of the negatives of this aspect would go away once purescript/spago#142 gets implemented.

[JordanMartinez]

As Spago continues to develop, I'm seeing less and less of a need for this issue. So, I'm going to close this.