When adding user paths, "*" paths are added to any platform-specific paths
Major enhancements to settings...

- Added meta settings, which begin with '@'. They are settings that do not participate in arguments and apply to all linters.
- @python[version] meta setting provides a cross-platform way to set the version of python to use.
- <script>@python[version] provides a cross-platform way to run a python script (such as pep8 and pyflakes) with a given version of python.
- Added shebang class attribute, if specified it is called with the first line of code and can return a setting.
- Added PythonLinter class, linters that subclass it have @python automatically added to their inline_settings, and get shebang support for setting @python.
- Added support for .sublimelinterrc settings files. This provides a way to specify settings for a tree of files without creating a project file.
- Fixed some problems with the building of the args map when a linter class is loaded.
- Added specific exception classes in except: statements.
PEP 257 says docstrings should use double quotes
No linter config should be in the main .sublimelinterrc
Fix gutter themes to be case-sensitive for case-sensitive file systems
Create the User gutter themes directory if it doesn't exist
Log success as well as failure when adding paths to be watched