An experimental redesign of magrittr

This is the initial commit of a redesign which takes a different
approach based on functional sequences.
Typo in test script
Now freduce handles invisible results
freduce now handles invisible results
Evaluation correction in wrap_function
nested dot rule instead of all dot-rule
Allow { } expressions
extractors, debuggers, and aliases.
More info on the branch in readme
spaces for tabs
some cleaning...
embed freduce in the functional sequence's environment. It needs to be available even if magrittr is not loaded, e.g. if %>% is imported.
Fixed evaluation bug of parenthesized expressions.
better naming...
"_fseq" --> "_function_list" in functions
Merge pull request #41 from steromano/patch-1

"_fseq" --> "_function_list" in `functions`
More documentation and a few fixes.
travis fix ?
Updated docs, vignette, and removed naming option in lambdas. Readme updated too.
Merge remote-tracking branch 'origin/master' into dev

merging dev into master