disable save button during image uploads

closes #1661

- disables save button at beginning of image upload
- enable save button at image upload fail, at image upload and download success and also at dropzone init
Fixes showing tag suggestions and tag container padding

fixes #1774
- Delayed showing the tag suggestions popup unless matching tags were found
- Changed the padding-left on the added tag container to 8px from 20px to fall in line with the left shadow overlay
Update CONTRIBUTING.md

fixing the doc as per discussed in the comments for pr/1824
Merge pull request #1826 from demesne/patch-2

Update CONTRIBUTING.md
Modified github.js to ensure __ isn't escaped at beginning of line

    fixes #1791
Added handling for undefined errors and test coverage

Fixes #1827
Merge pull request #1814 from cobbspur/uploadsave

disable save button during image uploads
Merge pull request #1828 from ddoolin/fix-tag-suggestion-and-padding

Fixes showing tag suggestions and tag container padding
Disabled styles for disabled buttons

Duh
Adds ability to quickly get to post’s edit page

fixes #1810

- updates frontend.single route to accept ‘edit’
as the last param

- updates controller.frontend to handle redirection
only when we would otherwise have rendered the page

- added unit tests for this behavior
Merge pull request #1819 from hswolff/quick-edit-post-redirect

Adds ability to quickly get to post’s edit page
Fix {{content words=“0”}} to actually return 0 words

fixes #1796

- adds in a workaround to the weirdness that currently
exists in downsize module
- adds tests
Remove express server from grunt test-coverage

- currently the coverage report only runs for unit & integration tests, and these don't need the express server.
Merge pull request #1831 from schneidmaster/fix-1827

Added handling for undefined errors and test coverage
Merge pull request #1840 from hswolff/fix-content-helper

Fix {{content words=“0”}} to actually return 0 words
Merge pull request #1821 from schneidmaster/fix-1791

Modified github.js to ensure __ is not escaped at the beginning of a line
Updated Casper to latest version

Fixes #1846
Remove successful login connections from the auth
throttle list

- once a user has successfully logged into ghost
they no longer are a malicious user and as such
their IP address should be removed from the
array of login attempts

- should also reduce the memory usage of Ghost
as the loginSecurity array gets pruned upon
every successful login

- this also fixes a race condition i was experiencing
during functional tests wherein i would receive
the login throttle message during regular testing.
Seems my machine is able to run casper fast enough
that it could complete each test under an amount
of time that tripped the login throttle message.
Merge pull request #1848 from schneidmaster/fix-1846

Updated Casper to latest version
Merge pull request #1850 from hswolff/fix-throttle-behavior

Remove successful login connections from the auth throttle list