Fix typo

"observale" => "observable"
Merge pull request #16 from ryngonzalez/patch-1

Fix typo
Corrected one typo(changed 'is has' to 'has' on line 134

There was a typo 'the first of which (perhaps called `arg1`) is has an LHS reference' on line 134 on in ch1.md. I have changed it to 'the first of which (perhaps called `arg1`) has an LHS reference'.
Merge pull request #17 from varun06/master

Corrected one typo(changed 'is has' to 'has' on line 134
Correct small omission in scope examples
Merge pull request #18 from lifebeyondfife/patch-1

Correct small omission in scope examples
could be a typo on line 88 

Line 88 says, "so he can access the variable a just as we'd see before". If we'd means we had, then we need to change the verb to 'seen'. 'before' kind of implies that it can be 'we had seen before'. I have made the change in the pull request.
Merge pull request #19 from varun06/patch-1

Small typo on line 88
changed some section titles in chapter 2
added chapter 3: 'Objects'
clarified titles
typo 'the' repeated two times 

'the' word is repeated. I have fixed the typo.
Merge pull request #20 from varun06/patch-2

typo -  'the' word repeated
Added more motivations for block-scope, corrected typos, clarified a few points
clarified some points around types and object sub-types
clarified some function vs. method details
TYPO: idenfify -> identify
Merge pull request #21 from dannyc/patch-1

TYPO: idenfify -> identify
Update ch3.md: missing semi-colon

Modified ch3.md example to include semi-colon after return object
Merge pull request #24 from alexreardon/patch-1

Update ch3.md: missing semi-colon