Explicitly check for Pathname

If the cover was html that included the Rails file path
(which is likely if it includes a wicked_pdf_*_helper),
this would incorrectly assume it to be a url or filename
instead of HTML content.
Update VERSION to 0.10.1
Check argument, not arg

If argument is a Pathname, arg is Pathname#to_s
Update VERSION to 0.10.2
Add the ability to create pdf from existing files in the filesystem without converting it to HTML
Print the chosen path when file does not exists

aids debugging on server
Merge pull request #306 from masterkain/patch-1

Print the chosen path when file does not exists
add :viewport_size option
fix identation in readme
Merge pull request #307 from eugene-ku/master

add support for viewport_size option
Merge pull request #303 from gizotti/master

Add the ability to create pdf from existing files
Update README.md

replace debuging with debugging
Merge pull request #309 from repinel/patch-1

Fix typo in README
Assemble wkhtmltopdf command as array of options, not a string.

The code previously did the moral equivalent of

  Open3.popen3("#{@exe_path} ... #{parse_options(options)} ...")

This causes a shell (e.g. bash on Linux boxes) to interpret the string,
which means that shell metacharacters in the values of some of the options
(e.g., ``) to cause weird and potentially dangerous effects.  Handing
popen3 a pre-parsed array of arguments gets the shell out of the way,
and eliminates the danger.
Merge pull request #311 from rst/popen3_array

Assemble wkhtmltopdf command as array of options, not a string.
Add option for no_stop_slow_scripts
Update VERSION to 0.11.0
fixed problem with generated html file path on windows
Fixed problem with generated html file path on windows
Fixed problem with generated html file path on windows