Replace virtcol() with len() in handleLeftClick().

When 'virtualedit' is set, the column where the cursor resides can no longer be
relied on for determining the number of elements in the 'line' list for
iterating.  Replacing virtcol() with len() seems to work correctly and not
result in E684 errors.  Fixes Issue #144
Better flow for renaming and deleting files

Previously when you delete or moved a file via
md or mm commands the NERDTree was asking you about what to do
with the remaining buffer of the just deleted or moved file. I
always press 'y' in this cases so I've decided to add a new parameter,
NERDTreeAutoDeleteBuffer which you can set to 1 in order to skip
this confirmation.
Better handling file renaming and deleting

If you are renaming a file via the mm hotkey and it is already opened then all
tabs and windows containing the old file will be replaced with a
new file. Current tab and windows structure is not changed anymore

If you are deleting a file via the md hotkey and it is already open, i.e.
presents in buffer lists then a buffer will be removed but a window and tab
will be kept with a ':enew' file
Fix typo in copy action
Merge pull request #196 from mark-rushakoff/master

Fix typo in copy action
Merge pull request #150 from cperl82/issue-144

Replace virtcol() with len() in handleLeftClick().
Merge pull request #191 from ZeusTheTrueGod/master

Improve handling obsolete buffers when renaming or deleting a file via the NERDTree 'm' menu
Fix call to globpath() for Vim 7.2 and below.

globpath() takes an extra optional parameter in Vim 7.3, but this
breaks NERD tree on earlier versions.
Merge pull request #200 from hpesoj/master

NERD tree doesn't currently work on Vim 7.2 and below.
Make NERDTreeFind work on hidden files
Make NERDTreeFind use an existing NERDTree window
Add a NERDTreeCWD command to change tree root to CWD
Merge pull request #202 from techlivezheng/feature/find-hidden-file

Make NERDTreeFind work on hidden files
add Path.isUnixHiddenFile and refactor to use it
Merge pull request #203 from techlivezheng/feature/find-in-existing-window

Reveal the current editing file in current NERDTree window instaead initiating a new one
Merge pull request #204 from techlivezheng/feature/chrootcwd

Add a NERDTreeCWD command to change tree root to CWD
Fix s:Path.Resolve to it handles '/' properly
Merge pull request #213 from cperl82/fixes

Fix s:Path.Resolve to it handles '/' properly
Added a frequently asked question to README
Merge pull request #219 from felipebueno/master

A question asked by many VIM / NERDTree newcomers