bug fixes

• add file to file copy
• add --delete option for find
• fix topn directory count.

with scp fix

Merge pull request #1 from fwang2/dev

build fix for scp

alpha with parallel copy function

v0.1-alpha2

minor build fix for linux

alpha with parallel copy function

v0.1-alpha

Merge branch 'master' of github.com:fwang2/pi