Tweaked progress bar animation
minor #17 Tweaked progress bar animation (1ed)

This PR was merged into the 1.0-dev branch.

Discussion
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Tweaked progress bar animation

Before:
![before](https://cloud.githubusercontent.com/assets/162986/4667182/5c288312-555a-11e4-848f-ffd6e278a18c.gif)

After:
![after](https://cloud.githubusercontent.com/assets/162986/4667184/600e8986-555a-11e4-89aa-e7ea9a62781e.gif)

I know it's subjective but I think the second one looks better. Tested on Ubuntu 14.04.

Commits
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ad899c8 Tweaked progress bar animation
Added a complete Symfony version checker to decide if we can install it
feature #29 Added a complete Symfony version checker to decide if we can install it (javiereguiluz)

This PR was squashed before being merged into the 1.0-dev branch (closes #29).

Discussion
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Added a complete Symfony version checker to decide if we can install it

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #25
| License       | MIT
| Doc PR        | -

Commits
-------

6b323fc Added a complete Symfony version checker to decide if we can install it
When no version is provided, the latest stable version of Symfony is installed
Tweaked progress bar animation
Added a complete Symfony version checker to decide if we can install it
feature #37 When no version is provided, the latest stable version of Symfony is installed (javiereguiluz)

This PR was merged into the 1.0-dev branch.

Discussion
----------

When no version is provided, the latest stable version of Symfony is installed

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #2
| License       | MIT
| Doc PR        | -

Commits
-------

1e9896c When no version is provided, the latest stable version of Symfony is installed
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/Symfony/Installer/NewCommand.php