Fix erroneous check for //objects

This was particularly detrimental on Windows, where it caused a slow
network lookup.

Closes #210.
Override 'shellslash' for external Windows command

With 'shellslash' set, tempname() returns a filename with forward
slashes, which trips up the type command if we don't translate to
backslashes first.

Fixes half of #212.
Add maps for resizing blame window
Follow symlinks

Previously, symlinks were not resolved. Thus, symlinks outside a git
directory would have no git dir even if they linked to a file in a git
directory.
Show diff from :Gstatus interally

When pressing enter on a header in :Gstatus, use :Git! rather than :Git
to show the diff.

Closes #208.
Re-enable editing files named index

This is a crude hack.  Watch for edge cases.

Closes #205.
Fix :Glog on Windows

Closes #199.
Revert "Follow symlinks"

This reverts commit 57af9b98cffbb5030b93eab8c26cb19f7f1f2ea6, which was
pushed by accident.
Don't activate maps without b:git_dir

Closes #227.
Encapsulate :Gstatus section determination logic
Fix - on :Gstatus headers
Centralize filename extraction in :Gstatus

This encapsulates some of the logic that will need to be updated to
solve #228.
Support localized `git status`

Closes #228.
Fix creation of files named index

Closes #231.
Support advice.statusHints = false

Closes #230.
Fix :Gstatus dd on unmerged path

Closes #240.
Fix :Gblame width with custom date format

Partially addresses #242.
Fix <C-W><C-O> in diff below :Gstatus

I'll admit I can't remember the original purpose of this code.

Closes #66.
Return to correct window when closing Gblame window

Vim does not guarantee persistent window numbers. Instead, windows are
numbered according to their position on the screen, with the topmost,
leftmost window always having number 1, and the bottommost, rightmost
window always having a number equal to the total number of windows
currently visible. Crucially, this means that, when a window is closed,
windows which come "after" it in the positional order will be
renumbered.

When fugitive's Gblame window is closed, e.g. by pressing `q`, it
attempts to return focus to the window of the blamed buffer. Previously,
the number of the window to return to was computed before closing the
Gblame window, then the Gblame window was closed, then the blamed
buffer's window was focused. However, since windows were often
renumbered as soon as the Gblame window was closed, this would
frequently cause focus to jump to the window *after* the blamed buffer's
window, rather than the intended behavior.

This corrects the issue by jumping to the proper return window prior to
deleting the Gblame buffer, ensuring that the computed window number is
in fact correct at the moment when the focus change occurs.
Accept a count with :Gstatus <C-N>/<C-P>