Set default values for sassc and sass-spec.
Enable autotools compilation on Travis.
Add --skip on Travis.

For personal development, it's good to stop on the first error, but for
CI, it's better to see the overall pass-fail rate.
Set up testing with autotools.
Enable autotools testing on Travis.
Remove -d for specifying spec directory.
Use automake's test driver.
Enable verbose output on Travis with automake.
Fix --skip in Travis with default Makefile.
Fix automake tests when sass-spec-dir is absolute.

It seems that automake gets confused with an absolute test path, even if
that path is contained in this directory. It doesn't seem to care if the
directory is outside the source directory, so we just make the absolute
paths relative. Not so easy in sh, but fortunately, we already require
ruby in this region of configure.
Provide a way to query all the imported files

This is very useful if you want to cache generated css and
need a way to invalidate the cache.
Fixed unitialized variable
Output the real path and not just the base path
Fix null & empty values printed in output

Declarations with value being a variable with an empty string or null was printed in output. Now, this is fixed in nested & compressed modes.

TODO: print declarations when the value is not a variable and directly a null value (sass official behaviour)
Fix gitignore
Merge pull request #168 from Nabellaleen/NullValuesFix

Fix null & empty values printed in output
merging in qulogics new auto conf
Merge pull request #161 from hanikesn/output_included_files

Provide a way to query all the imported files
Update Readme.md

Fix links to SassSpec and SassC. The Markdown links were inverted.
Merge pull request #171 from molily/patch-1

Update Readme.md