ini: support Python multi-line values (#145)

* [GH-144] Support Python multi-line values

ini.go

@@ -140,6 +140,11 @@ type LoadOptions struct {
 	// AllowNestedValues indicates whether to allow AWS-like nested values.
 	// Docs: http://docs.aws.amazon.com/cli/latest/topic/config-vars.html#nested-values
 	AllowNestedValues bool
+	// AllowPythonMultilineValues indicates whether to allow Python-like multi-line values.
+	// Docs: https://docs.python.org/3/library/configparser.html#supported-ini-file-structure
+	// Relevant quote:  Values can also span multiple lines, as long as they are indented deeper
+	// than the first line of the value.
+	AllowPythonMultilineValues bool
 	// UnescapeValueDoubleQuotes indicates whether to unescape double quotes inside value to regular format
 	// when value is surrounded by double quotes, e.g. key="a \"value\"" => key=a "value"
 	UnescapeValueDoubleQuotes bool