Updates to submodules

Submodule bundle/ruby-vim a7b0b38..3ffc0aa:
  > Make two related patterns consistent
  > Fix issue with required keyword args
  > Also skip matchit matches that are regexes
  > Merge pull request #204 from glucero/master
  > Merge pull request #197 from robertomiranda/rails-4
  > Merge pull request #192 from jvirtanen/features/cocoapods
  > Remove Gem installation infrastructure
  > Apply real fix for Andy Wokula's HTML indent
  > Merge pull request #196 from rbright/master
  > Merge pull request #194 from bk2204/highlight-regex-in-hash-key
Submodule bundle/vim-fugitive 546a6bf..152c919:
  > Check `&diff` first in fugitive_diff autocmds
  > Fix version regex
  > Improve heuristics for status section detection
  > Place extra emphasis on a clean history
  > Look for $GIT_DIR and $GIT_WORK_TREE
  > Store more than just dir in s:temp_files
  > Respect GIT_CEILING_DIRECTORIES
Submodule bundle/vim-git 104636f..80d2c77:
  > Merge pull request #23 from dcbaker/fix-gitsendemail
Submodule bundle/vim-json 752e607..c3895dd:
  > Merge pull request #24 from DouglasLivingstone/patch-1