installing latest stable release and git built fish versions

bucaran-fish-spec

+ Add fish eval fix See #fish-shell/pull/1892
+ New and improved output system with colors, etc.
+ Support for multiple non-nested describe blocks.
+ Remove spec.log and favor `msg` plugin and standard echo.
+ `spec.eval` no longer evaluates multiple functions, acting now as a simplified
  router between the view `spec.view` and the controller `spec.run`.
+ Add new `spec.view` to act as a hub for all test output.
+ Add report with passed/failed tests to `spec.view`
+ Now test descriptions are used directly from the function name. Description
  fields are now optional.

changing installer to use travis ci env vars

run tests from correct repo on travis

Enable peco plugin to take current commandline as query

Fixes bak assertions

Modifying bak plugin tests to use fish spec

Do not add test/spec files to function path in _prepend_tree.

Make sure to exit with 0 of 1 when reloading the framework

run all tests, including plugins tests, on travis