Tweaking header sizes

This changes the headers sizes to span from 1.0 to 2.0 times the
size of the default font.
Merge pull request #102 from damiancarrillo/i95-header-size

Tweaking header sizes
Add usage to the Android readme
Merge pull request #104 from DDRBoxman/master

Add usage to the Android readme
Improving iOS README.md
Merge pull request #105 from damiancarrillo/ios-readme

Improving iOS README.md
Update README.md
Update README.md
Update README.md
Update README.md
Updating the sample markdown

This matches what is displayed on the bypass home page.
Updating to have an even smaller header
Merge pull request #109 from damiancarrillo/sample-markdown

Updating the sample markdown
Check for null parent in recureElement

The check is done elsewhere in this method, it should be done here as
well
Merge pull request #118 from JimiSmith/master

Check for null parent in recurseElement
fix crash when tap on an empty UITextView

Well, in this case, I think we should have to check UITextView is not empty at first.
Otherwise, this will causes an exception:
`'NSRangeException', reason: 'NSRLEArray objectAtIndex:effectiveRange:: Out of bounds'`
Merge pull request #119 from vinhnx/master

Fix crash when tap on empty UITextView
Rendering single page markdown correctly

A problem occurred in the rendered output whenever the body of
content was smaller than a single page (basically, the content
fit inside of the visible bounds of the markdown view).

This fixes that problem.
Merge pull request #121 from Uncodin/i9-bottom-display

Rendering single page markdown correctly
Create skewed font if italic font is not found. Assert that fonts exist instead of crashing later.