Squashed commit of the following:

commit a59659655c0464bf87f97cd6c9fff87924537468
Author: Denis Sikuler <mforeg@yandex.ru>
Date:   Sun Jun 1 23:12:21 2014 +0400

    Change order of parameters for runNpmInstall

commit 468708943e43e68b57bab70abf7d70fd68d3157b
Author: Denis Sikuler <mforeg@yandex.ru>
Date:   Sun Jan 12 16:41:29 2014 +0400

    Fix prompt.sanitizeYesNo for y/N answer

    Fixed `prompt.sanitizeYesNo` function so that `y/N` value is converted
    into `false`.

commit 01f6e522cff691afc7b4c57b2f7311299f250ce9
Author: Denis Sikuler <mforeg@yandex.ru>
Date:   Sun Jan 12 15:01:36 2014 +0400

    Use project's name as default repository name

commit cd5e013016d0426d113fc420dd502cc66fde8f6f
Author: Denis Sikuler <mforeg@yandex.ru>
Date:   Sat Jan 11 21:19:29 2014 +0400

    Add keywords and npm_install prompts, two helpers

    Added:
    * two built-in prompts: `keywords` and `npm_install`
    * `prompt.sanitizeYesNo` to convert `yes/no` answers into boolean values
    * `init.runNpmInstall` to run `npm install` command
    * basic support for `github_user` key in `defaults.json`

Closes gh-69.