add install command
add install:bower command
add install:npm command
Merge pull request #2800 from jakecraige/install

Add ember install commands
Update package.json
Update README.md
Update README.md
Update README.md
Exit with non-zero for unknown commands.
Merge pull request #2816 from rwjblue/fail-build

Exit with non-zero for unknown commands.
Allow test framework addons to override query string.
Merge pull request #2820 from rwjblue/test_page-query-string-abstraction

Allow test framework addons to override query string.
Bump ember-cli-dependency-checker to v0.0.7

This also fixes #2591.
Merge pull request #2821 from quaertym/patch-15

Bump ember-cli-dependency-checker to v0.0.7
Change to more robust file checking

The `isFilePath` function simply checked for the presence of a period in the output path. This isn't a reliable way to detect files vs. directories (directories can have periods in their names, and files don't have to).

This switches to using `fs.statSync` to check if `stat.isFile()` is true, which actually detects files vs. directories.
Merge pull request #2719 from davewasmer/patch-3

Change to more robust file checking