Added .gitignore
Added .gitignore

Joozt83/html-to-markdown,jarnix/html-to-markdown,TomzxForks/html-to-markdown,Synchro/html-to-markdown,nickcernis/html-to-markdown,thephpleague/html-to-markdown,deadflowers/html-to-markdown,nickcernis/html-to-markdown,jeremykenedy/html-to-markdown,thephpleague/html-to-markdown,WouterSioen/html-to-markdown