Crash fixes while custom truncation

The following things has been fixed.

1. Crash fixes
2. fixed highlighting pattern
3. detection of adjacent patterns

Minor fix for Highlight color

Bug fix: text NSForegroundColor restored when highlighting ends

Major change in Drawing Code

Truncation is appended in drawTextInRect method. This is because at this point, we have correct size of text container.

Advance Configuration For Truncation Token

This release has the following features:

1. Truncation token can be set from the interface builder.
2. Custom truncation can be enabled/disabled by toggling a bool in the interface builder.
3. Now image can be set as truncation indicator.

Feature: Highlight on Tap

The patterns can be highlighted when they are tapped. To highlight patterns, the attributes RLHighlightedForegroundColorAttributeName and RLHighlightedBackgroundColorAttributeName should be set.

Minor Feature Update

Added support for making array of strings clickable.