Pass element not jQuery object as target

Previously this was passing since ctrl-z was completely unbound at
this point which isn't the case on Windows.
Use temp directory in checkoutHead specs
Use temp directory in isPathNew/Modified specs
Add copyRepository helper
Remove spec completely tested in git-utils library
:lipstick:
Move fixtures into repo
Copy repository in remaining specs
Set project path to temp working directory
Copy repository to temp folder
Remove # which is interpreted as a tag

This spec was not running because of it since
jasmine-tagged is configured to filter tags by
process.platform
Enable core specs when run outside of clone repo

The failing specs have been updated so that specs
can now run without the requirement of a Git repository
at the root.
Use forward slash on all platforms

Paths are normalized by git-utils to use / on all platforms
Upgrade to first-mate@1.6.1
Write removed file to temp directory
Merge pull request #2462 from atom/ks-windows-spec-fixes

Get core specs green on Windows