* Fix escaped regex values in Python client (#1517).
* Override PythonClientCodegen toRegularExpression() method to correct
issue with backslashes being escaped. This issue was a result of
calling escapeText() in the parent DefaultCodegen class.
* Only escape unescaped forward slashes in PythonClientCodegen.
* Override addRegularExpressionDelimiter in PythonClientCodegen.java
such that only unescaped forward slashes in the pattern get escaped.
* Adds a new test resource .yaml file for specifically testing this
issue.
* Check for regular expression modifiers in PythonClientCodegen.
* Adds check in postProcessPattern() in PythonClientCodegen.java to
check if regular expression has modifiers defined. If so, it throws an
exception as modifiers are not currently supported in the Python
client.
* PythonClientCodegen warns that regex modifiers are not supported.
* Changes behavior in PythonClientCodegen.java to no longer throw an
IllegalArgumentException in the case that a pattern contains
modifiers. A warning message will be logged instead stating that
modifiers are not currently supported by the codegen class.
* Remove warning for PythonClientCodegen regex modifier support.
* Removes warning message from PythonClientCodegen.java stating that
regular expression modifiers are not currently supported. Further
code review and testing revealed that this feature is already
supported and working.
* Add updated Python client sample files.
