Log Message:
Update to 3.1.2

Changes in 3.1.2:
    Add missing file to extra-source-files 
Changes in 3.1.1:
	Bug fixes (#24, #30, #31, #32)

( #32 => https://github.com/simonmar/alex/pull/32 )
( #31 => https://github.com/simonmar/alex/pull/31 )
( #30 => https://github.com/simonmar/alex/pull/30 )
( #24 => https://github.com/simonmar/alex/pull/24 )