configure.ac: Check for the presence of pango 1.22.0 or higher
configure.ac: Check for the presence of pango 1.22.0 or higher

Tesseract's training tool text2image uses these two functions: 
pango_glyph_item_iter_init_start
pango_glyph_item_iter_next_cluster

That means it requires Pango >=1.22.0:
https://developer.gnome.org/pango/stable/api-index-1-22.html
https://developer.gnome.org/pango/stable/pango-Glyph-Storage.html#pango-glyph-item-iter-init-start
https://developer.gnome.org/pango/stable/pango-Glyph-Storage.html#pango-glyph-item-iter-next-cluster
tesseract-ocr/tesseract,UB-Mannheim/tesseract,jbarlow83/tesseract,amitdo/tesseract,amitdo/tesseract,stweil/tesseract,stweil/tesseract,amitdo/tesseract,amitdo/tesseract,UB-Mannheim/tesseract,jbarlow83/tesseract,amitdo/tesseract,tesseract-ocr/tesseract,jbarlow83/tesseract,tesseract-ocr/tesseract,stweil/tesseract,tesseract-ocr/tesseract,jbarlow83/tesseract,stweil/tesseract,jbarlow83/tesseract,tesseract-ocr/tesseract,UB-Mannheim/tesseract,stweil/tesseract,UB-Mannheim/tesseract,UB-Mannheim/tesseract