Allow config files to have any name (fixes #486).

Currently require is used to load and parse the config file. Unfortunately this forces the filename extension to be .json.

As discussed in https://github.com/eslint/eslint/issues/486, the consensus was that since config files should be JSON and not executable code, the .json restriction is unnecessary and it is preferable to parse the file ourselves instead of using require (which ultimately does exactly what this commit does).
Fixing broken links in documentation
Update no-extra-semi.md

Accidentally, the last paragraph was part of the last code block.
Update no-new.md

"the" follows another "the"
Merge pull request #539 from ruffle1986/patch-2

Update no-new.md
Merge pull request #538 from ruffle1986/patch-1

Update no-extra-semi.md
Merge pull request #537 from ilyavolodin/Documentation

Fixing broken links in documentation
Merge pull request #535 from aparajita/parse-json

Allow config files to have any name (fixes #486).