Add Paddle OCR as The Local Text Detector

1. Add a Paddle option to text detection. Paddle OCR is local detector without the need for network connection (unlike Google OCR through API).
2. No change for other part at all

[14/9/2021] Perceptual Grouping Site Release Version

1. Merge text contained in the non-block compo
2. Add merge line to paragraph

Add Block Recognition for Non-text Elements

Block is a rectangle border enclosing a group of compos (consider it as a wireframe)

In the non-text element detection:

1. Recognize blocks from all non-text elements
2. Do not merge elements contained in a Block

UIED with Google OCR

1. Tidy up and simplify the code
2. Replace EAST with Google OCR to detect GUI text
3. An more efficient merging approach to merge the non-text and text detected elements

UIED Version Archive

Archive the old version before the upgrade and refactoring for the record.

Significant Speed Improvment

1. Significant speed improvement for UIED (500%)

2. Add adjustable track bar for testing

Configurable Key Parameters

Extract all key parameters as configurable, including:

    ele:min-grad: gradient threshold to produce binary map         
    ele:ffl-block: fill-flood threshold
    ele:min-ele-area: minimum area for selected elements 
    ele:merge-contained-ele: if True, merge elements contained in others
    text:max-word-inline-gap: words with smaller distance than the gap are counted as a line
    text:max-line-gap: lines with smaller distance than the gap are counted as a paragraph

v2.0

 update reademe