Updated README.md, History.md, and License formatting. Added new CLI options. By @XhmikosR.

* switch back to code blocks instead of inline code
* remove the closing hashes from paragraphs since they are not needed
* break a couple long lines
* cli: accept more synonym switches like --empty and --keepbreaks
* README.md: document the command line switches. This fixes issue #41.
* LICENSE: break the lines