spiderforacs

This script is used for downloading PDF files from ACS publication. User guide:

For spiderforacs.py:
Input a keyword. If keywords, use "+" to connect them.
![Image text](https://raw.githubusercontent.com/pyforspider/spiderforacs/master/example/spiderforacs.bmp)

For tit_abs.py:
Input a keyword. Get your report back.
![Image text](https://raw.githubusercontent.com/pyforspider/spiderforacs/master/example/tit_abs.bmp)