Fix Enum.uniq/2 spec
Merge pull request #1208 from mururu/fix-spec

Fix Enum.uniq/2 spec
Remove unneeded `case`

`:os.type/0` always returns a tuple in R16B
to_binary for URI.Info do not ignore the path
Merge pull request #1209 from mururu/rm-case

Remove unneeded `case`
Convert project stack to records
Merge pull request #1211 from mururu/to-binary-uri-path

to_binary for URI.Info do not ignore the path
Dont run any tasks recursively from another task

The only time a task may run recursively is after a new project has been pushed to the stack.
Merge pull request #1198 from ericmj/patch-1194

Dont run deps tasks recursively when they are started non-recursively
Optimize downcase, upcase and rstrip in Unicode
No need for accumulator on downcase/upcase
Add a few sanity check tests for upcase & downcase
removed use of local variables in shell scripts in order to remove dependency on bash
Merge pull request #1218 from zambal/remove-bash-dependencies

remove dependency on bash in shell scripts
Improve error message for diverged deps
Merge pull request #1217 from ericmj/mix-outofdatedepserror

Improve error message for diverged deps
Add a --force option to `mix local.install`.

Useful for makefiles.
Added more informative error to Makefile when ex_doc is not available.

Added more information to README about building docs.

fixes #1151
Merge pull request #1221 from alexrp/mix-local-install

Add a --force option to `mix local.install`.
Merge pull request #1222 from jjh42/doc-error

Added more informative error to Makefile when ex_doc is not available.