pango rbpangoattrlist.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoanalysis.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangomatrix.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangofont.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoitem.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangolanguage.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoglyphstring.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangologattr.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoscriptiter.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoprivate.h: drop PANGO_CHECK_VERSION(1,10,0)
pango rbpangoglyphitem.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangofontmetrics.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangocairocontext.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangoattributes.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangofontface.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangofontfamily.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpangofontmap.c: drop PANGO_CHECK_VERSION < 1.14
pango rbpango.h: drop PANGO_CHECK_VERSION < 1.14
add required libpango version
update READMEs