fs.find() on win32-msys undesired behaviour

[arch-jslin]

everything is alright when using cmd.exe on win32 platform,
but I have a need to use luarocks in msysgit environment,
and the fs.find() with msys' find command produced undesired
behaviour, causing rock deployment while using msys impossible.

I changed following lines of luarocks.fs.win32.tools:
248:
-- Windows find is a bit different
if file:sub(1,2)=="." then file=file:sub(3) end
if file ~= "." then
...

to
248:
-- Windows find is a bit different
if file:sub(1,2)=="." then file=file:sub(3) end
if file:sub(1,2)=="./" then file=file:sub(3) end --the added line
if file ~= "." then
...

[hishamhm]

Fix committed!