add setup for idl-mode
disable vim in undo-tree-mode, tweak undo-tree-setup
define get-region-bounds, use it in generated align functions

New function `get-region-bounds' is necessary because
linewise vim region is reported incorrectly by
region-beginning & region-end pair if functions, but
block type of region is not handled yet.
fix long lines highlighting
add completion of language extension to #lang abbrev, define haskell-help-for-symbol-at-point

Function haskell-help-for-symbol-at-point provides generic documentation
about various symbols. For now in provides documentation for language
extensions of ghc 7.6.3.