fix_duplicating_css_ids_bug: generate id with prefix
refactor
If nil return value, use the form buffer instead

closes #887
Merge pull request #1991 from joxxoxo/fix_duplicating_css_ids_bug

namespace hidden field IDs
refactor breadcrumb helper

+ ActiveRecord#find accepts a string (even when searching for a numeric ID)
+ removed unnecessary begin/rescue/end block; used nil-returning method alternatives
+ use `path` instead of `fullpath` to get rid of query parameters (we already leave them out)
Merge pull request #1938 from Daxter/refactor/breadcrumb-helper

Refactor breadcrumb helper
Merge pull request #1996 from Daxter/bugfix/887-form-buffers

[887] Respect the form buffer!
rollback shoulda-matchers
Merge pull request #2004 from Daxter/bugfix/rollback-mocha

Rollback mocha / shoulda-matchers