Support two text encodings at once

This is a new build for Windows, based on the July 2017 ag 2.0.0 sources.

• Supports Windows XP and newer versions of Windows. (Windows Server 2003 minimum for the 64-bits version.)
• Supports path names up to 64KB. (Using WIN32 APIs not limited to 260 bytes, even in XP.)
• Supports Unicode path names.
• Supports symbolic links and junctions.
• Supports text files encoded both in UTF-8 and in the current Windows System Code Page.
  (The latter depends on the Windows localization. Ex: CP 1252 for US and West-European versions of Windows.)
• Supports Unicode search strings and regular expressions.
  (Some limitations for regexps searches in files encoded in Windows system CP, especially for MBCS CPs.)
• Outputs non-ASCII characters correctly in any console code page.
  (Provided that the console font has bitmaps for them. See the table below.)
  (But if the output is piped to a file or another program, it'll be converted to the current console code page,
  and unsupported characters will be lost. This is a limitation of the Windows console, not of ag.exe.)

The zip file contains 32 and 64-bits ag.exe versions.

Console font	Character families it can display
Arial sans MS	Latin; Greek; Cyrillic
Liberation Mono	Latin; Greek; Cyrillic; Hebrew
Microsoft YaHei	Latin; Greek; Cyrillic; CJK Ideograms; Hiragana; Katakana; Hangul
Yu Gothic	Latin; Greek; Cyrillic; Dingbats; CJK Ideograms; Hiragana; Katakana