Parse options file options

- this proof-of-concept code duplicates OptionParser information to
   get something going
 - take care to respect the type of each option from the OptionParser

lib/github_changelog_generator/parser_file.rb

@@ -23,9 +23,7 @@ module GitHubChangelogGenerator
 
     def parse_line!(line)
       key_sym, value = extract_pair(line)
-      value = true if value =~ /^(true|t|yes|y|1)$/i
-      value = false if value =~ /^(false|f|no|n|0)$/i
-      @options[key_sym] = value
+      @options[key_sym] = convert_value(value, key_sym)
     rescue
       raise ParserError, "Config file #{file} is incorrect in line \"#{line.gsub(/[\n\r]+/, '')}\""
     end
@@ -38,5 +36,23 @@ module GitHubChangelogGenerator
       key, value = line.split("=", 2)
       [key.sub("-", "_").to_sym, value.gsub(/[\n\r]+/, "")]
     end
+
+    KNOWN_ARRAY_KEYS = [:exclude_labels, :include_labels, :bug_labels,
+                        :enhancement_labels, :between_tags, :exclude_tags]
+    KNOWN_INTEGER_KEYS = [:max_issues]
+
+    def convert_value(value, key_sym)
+      if KNOWN_ARRAY_KEYS.include?(key_sym)
+        value.split(",")
+      elsif KNOWN_INTEGER_KEYS.include?(key_sym)
+        value.to_i
+      elsif value =~ /^(true|t|yes|y|1)$/i
+        true
+      elsif value =~ /^(false|f|no|n|0)$/i
+        false
+      else
+        value
+      end
+    end
   end
 end