Merge pull request #142 from wmathurin/unstable

fixing typo
Change version number to 2.1.0
Merge pull request #143 from bhariharan/master

Getting Ready to Release ```v2.1.0```
Changing version to 2.2.0.unstable
Merge pull request #144 from bhariharan/unstable

Merging back from master to unstable with new version name
Add entry for HybridFileExplorer in README
Fix typo
Merge pull request #145 from bhariharan/master

Add entry for HybridFileExplorer in README
Merge branch 'master' into unstable
Merge pull request #146 from bhariharan/unstable

Merge 'master' into unstable
Latest dev guide PDF
Merge pull request #147 from bhariharan/master

Latest dev guide PDF
Merge branch 'master' into unstable
Merge pull request #148 from bhariharan/unstable

Merge branch 'master' into unstable
Replacing PDF with errors
Merge branch 'master' into unstable
Merge pull request #149 from bhariharan/unstable

Merge 'master' into unstable
fix error is not defined bug.

the method is `fail`,but used the `error`
Updating Connected App instructions.
Merge pull request #150 from dozer47528/master

fix error is not defined bug.