ncurses 6.1 - patch 20191012

ncurses 6.1 - patch 20191012

+ amend recent changes to ncurses*-config and pc-files to filter out
  Debian linker-flags (report by Sven Joachim, cf: 20150516).
+ clarify relationship between tic, infocmp and captoinfo in manpage.
+ check for invalid hashcode in _nc_find_type_entry and
  _nc_find_name_entry.
> fix several errata in tic (reports/testcases by "zjuchenyuan"):
+ check for invalid hashcode in _nc_find_entry.
+ check for missing character after backslash in fmt_entry
+ check for acsc with odd length in dump_entry in check for one-one
  mapping (cf: 20060415);
+ check length when converting from old AIX box_chars_1 capability,
  overlooked in changes to eliminate strcpy (cf: 20001007).
+ amend the ncurses*-config and pc-files to take into account the rpath