yasnippet: only fetch snippets submodule
yasnippet: remove :features and customize hacks

yasnippet now uses load-file-name to come up with a reasonable default
for yas-snippet-dirs.
byte-compile yasnippet.el

It's unclear why compilation was avoided initially[1], but it seems to work
now.

[1]: SVN problems? https://github.com/dimitri/el-get/issues/200
Remove useless features from bar-cursor package recipe.
Use :prepare instead of :features in auto-capitalize package recipe
Merge pull request #1618 from cybem/bar-cursor

Remove useless features from bar-cursor package recipe.
Merge pull request #1619 from cybem/auto-capitalize

Use :prepare instead of :features in auto-capitalize package recipe
Merge pull request #1577 from npostavs/yasnippet-simplify

Yasnippet: avoid yasmate submodule, and remove hacks