Merge pull request #523 from zenorocha/patch-1

Use SVG badge for Travis
bump deps
code style
main.js => index.js
Fix `#determineAppname()` to always find a name
Feature Base#gruntfile expose a gruntfile-editor API

That allow multiple generator from adding configurations to the
gruntfile.js without creating conflicts when writing the file.
Merge pull request #525 from SBoudrias/gruntfile-api

Gruntfile api (Fix #432)
Check for git prior to calling shell.exec
Merge pull request #532 from TheAlphaNerd/master

Check for git prior to calling shell.exec
Add comment for registerValidationFilter entries.
Typo correction in methodIsValid comment
Fix task queue names
Version 0.17.0-pre.3
Changes appendStyles and appendScripts to be a compelete alias to appendFiles

See #536
Merge pull request #537 from oliverh855/patch-1

Changes appendStyles and appendScripts to be a compelete alias to appendFiles
Clarify assert.file API documentation
Allow helpers.mockPrompt to work without arguments

Fix #538, fix #539
"Description" help text + general cleanup

Squashed commits:
[f6d094a] PR review changes
[cdb4485] description help text for arguments

- removed unused `help.bannerFor()`
- updated some JSDoc
- option defaults no longer display if default value is an empty string
- rewrote unit tests for `help.help()` function
    - the old tests made it difficult to debug since Mocha would only report truthiness
    - using the updated method, we now compare strings and can easily see any differences as reported by the assertions
    - I also elected to ignore extra whitespace here, because I want to test the content; not the `text-table` module's output.
[8ad7e91] general cleanup: removing some unused vars, updating some JSDoc tags & comments, simplified expression
Merge pull request #534 from boneskull/master

Small updates to "help"
Fix a RunContext so it run only once

There was a race condition causing a generator to run multiple times if
the temp directory rimraf action was too fast.