Creates links with mklink instead of junction

I don't think junction.exe ships with Windows, but everything post Win7
ships with mklink.exe. Update to the new hotness.

I can get old junction-style links with /J but I see no reason to do
that.

Untested.
Make TranslateKnownLinks use a list of known_pairs

Instead of the single vim pair, support an arbitrary list of pairs and
add c:/bin (linked to my work directory).

Tested with something in bin and on followsymlink.
Use noremap in cscope_maps and disable unsplit

Disable the unsplit maps -- I don't use them at all. Use noremap on the
split maps (I don't use them often either).

I should probably rewrite this to use AsyncCscopeFindX.
Fix cpp ftplugin to be buffer-specific

Move SwitchSourceHeader function into autoload. This is the cpp-specific
one (with specific file extensions), so it is in a cpp.vim file.

Fix global changes (iabbrev and map) to be buffer-specific.

loaded_cpp_extra is now meaningless because everything is
buffer-specific. It was wrong in the first place.
Disable tearoff menus and fancy tabline (in win32)

I don't use tearoff menus anymore, so disable them (I only have the
menubar for when other people come to my desk).

Disable the fancy tabline in Windows. It causes vim to re-position
itself when it creates the tabline (because it's using the gui system's
tabs). Without this option, it uses ascii tabs which look bad, but I
don't use tabs often so I can deal.

Source for tabline fix:
http://stackoverflow.com/questions/13251522/why-does-gvim-resize-and-reposition-itself-after-some-actions
Try using vim with no menubar for a bit

I don't use the menubar, but sometimes coworkers do. Let's see if it's
worth keeping. Vim looks so much more full screen now.
Update autohotkey to put thin window on left monitor

My game is on my left monitor now, so update the position.