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
Fixing 404 on page view when using PostgreSQL

closes #1801
- adding fixBools method to `server/models/base.js` to convert bools to 1/0 to be consistent with MySQL & sqlite3 data providers (based on @ErisDS recommendation)
- this in turn fixes the check in `server/controllers/frontend.js`, which does an explicit `post.page === 0` comparison (in pgsql this is a `boolean`, since the schema declares it as "bool" in `server/data/schema.js`, but MySQL/sqlite3 don't have concept of Boolean, only an integer or bit)
- any model retrieved from persistence will pass through this (possible future refactoring is to combine fixBools & fixDates into one "canonicalize()" to have a single loop pass)
Merge pull request #1849 from gimelfarb/fix-1801-pg-404

Fixing 404 on page view when using PostgreSQL
Improving regexes in functional tests

- being more explicit about what resources we expect to load after saving
  a post
- should prevent #1839 from failing tests
Merge pull request #1857 from ErisDS/regex-test-fixes

Improving regexes in functional tests
New URL helper - URL consistency fixes

fixes #1765
fixes #1811
issue #1833

New UrlFor functions

- moved body of url helper to config.path.urlFor, which can generate a URL for various scenarios
- urlFor can take a string (name) or object (relativeUrl: '/') as the first
  argument - this is the first step towards issue #1833
- also added config.path.urlForPost which is async and handles getting
  permalink setting
- frontend controller, ghost_head helper, cache invalidation all now use
  urlFor or urlForPost all urls should be correct and consistent

URL Consistency Improvements

- refactored invalidateCache into cacheInvalidationHeader which returns a
  promise so that url can be generated properly by urlForPost
- moved isPost from models to schema, and refactored schema to have a tables object
- deleted posts now return the whole object, not just id and slug,
  ensuring cache invalidation header can be set on delete
- frontend controller rss and archive page redirects work properly with subdirectory
- removes {{url}} helper from admin and client, and replaced with adminUrl
  helper which also uses urlFor
- in res.locals ghostRoot becomes relativeUrl, and path is removed
Merge pull request #1817 from ErisDS/url-helper

New URL helper - URL consistency fixes
Unique filenames for tmp files in ghost-busboy

fixes #1843

- uses a timestamp and an md5 hash of the filename for the tmp file
  instead of the user-provided filename
Merge pull request #1851 from seanhellwig/master