Bumping version to 0.1.1
Moved the `clearAuthorizationHeader` call

This allows authorization to be set, and used, outside the call to
`authenticateUsingOAuthWithPath...`
Update README.md

Fixes #36
Adding documentation

Minor reformatting
Rename kAFOAuthCredentialServiceName to kAFOAuth2CredentialServiceName

Fixes a duplicate symbol error when linking to AFOAuth1Client.
added link for 0.1.1 docs in readme.
import frameworks in pch file
storeCredential:withIdentifier extended to allow selection of security accessibility while providing a decent default.
Merge pull request #56 from Miners/master

Allows specification of kSecAttrAccessible attribute
Merge pull request #48 from ejensen/patch-1

Rename kAFOAuthCredentialServiceName to kAFOAuth2CredentialServiceName
Merge pull request #49 from westonplatter/master

added link for 0.1.1 docs in readme.
Editing section about documentation
Merge pull request #52 from hwaxxer/cocoapods-warning

import frameworks in pch file
[Issue #38] Allow for nil refresh token when setting expiration of credential
Merge pull request #33 from tnwinc/master

Allow `setAuthorizationHeaderWithUsername` to work when called before getting OAuth credentials.
[Issue #33] Removing unnecessary call to -clearAuthorizationHeader in authenticateUsingOAuthWithPath:...
Bumping version to 0.1.2
Adding #ifdef around kSecAttrAccessibleWhenUnlocked to prevent build error on OS X < 10.9
Merge branch 'ghmaster' into experimental-oauth-2-error-response

# By Mattt Thompson (7) and others
# Via Mattt Thompson
* ghmaster:
  Adding #ifdef around kSecAttrAccessibleWhenUnlocked to prevent build error on OS X < 10.9
  Bumping version to 0.1.2
  [Issue #33] Removing unnecessary call to -clearAuthorizationHeader in authenticateUsingOAuthWithPath:...
  [Issue #38] Allow for nil refresh token when setting expiration of credential
  Editing section about documentation
  storeCredential:withIdentifier extended to allow selection of security accessibility while providing a decent default.
  import frameworks in pch file
  added link for 0.1.1 docs in readme.
  Rename kAFOAuthCredentialServiceName to kAFOAuth2CredentialServiceName
  Adding documentation
  Update README.md
  Moved the `clearAuthorizationHeader` call
  Bumping version to 0.1.1