Update writing_modules documentation: CasperJS in now able to call/load nodejs modules

The same way phantomJS can.
Refactor to remove unnecessary entries in paths array
Merge pull request #588 from hexid/refactor-bc

Refactor to remove unnecessary entries in paths array
Add a better sample of nodejs modules integration https://github.com/n1k0/casperjs/pull/587
Update writing_modules.rst
Update writing_modules.rst
Update writing_modules.rst,"n1k0 compliant" :)
Merge pull request #587 from mickaelandrieu/master

Update writing_modules documentation: CasperJS in now able to call/load ...
Typo fix in the page.error documentation
Merge pull request #595 from bp323/docTypo

Typo fix in the page.error documentation
XML serialization for xUnit output
Merge pull request #605 from fdubost/master

XML serialization for xUnit output
Fixes a regression on sub module loading

CasperJS didn't find any more users modules, when we
indicate only the name of the main script (it worked only
when we indicate the full path of the script on the command line).

Fixes #601
Cli tests: adds the casperjs output in command errors
clitests: Fixes issue with phantomjs path

In travis environment, PHANTOMJS_EXECUTABLE contains a relative
path to phantomjs executable.

However, new tests change the working directory, so this path becomes
invalid. We should set PHANTOMJS_EXECUTABLE to an absolute path.
Fix typo base46 -> base64
Merge pull request #614 from johndouthat/patch-1

Fix typo base46 -> base64
introduce new assertInstanceOf() method
minor syntax fix
Correct method, tests and documentation