Correct .gitignore syntax and remove compiled bootstrap.json file at root.

Prior to this commit, the git repo was omitting files from the
generated directories (build/, phonegap/, node_modules/) but not their
respective subdirectories. This commit corrects .gitignore syntax to
ensure these subdirectories do not get re-introduced to the project.

This commit also removes the bootstrap.json file at the root of the
project as it is also generated on 'sencha web start' and 'sencha app
build'.
Add native/ directory to .gitignore

New Sencha Cmd versions will output local cordova/phonegap build
results to a directory called "native" at the project root. This
commit adds a clause to the .gitignore to ensure that this new build
directory does not pollute the repo.
Remove bootstrap.js and resources/css/app.css from project

The bootstrap.js and resources/css/app.css files were included in the
.gitignore file as they are compiled resources, but they were not
actually removed from the project repository. This commit removes
these files from the repository.
Merge pull request #12 from osu-cass/maint-gitignore-buildfile-subdirectories

Maint gitignore buildfile subdirectories
Update readme documents

I updated our readme documents to reflect our projects structure and
function. I wrote them in such a way as to make it easy for future
developers to get an idea of how our project is set up and how the
multiple pieces interact.
Update readme style 1

Added subheaders and bulleted file names, also made each folder item a new
paragraph.
Update readme style 2

Added newlines and fixed points for files.
Update readme style 3

Updated the main readme to include info about file structure.
Update readme style 4

Updated the main readme with file structure and added a readme to the
phonegap folder to explain how we instantiated our splash screen.