hterm 1.1, Grab bag of fixes.

* Fix base64 encoding of the bell audio.
* Reset the vt object when terminal is reset.
* Break out of a parseUntilStringTerminator_ if an embedded ESC is
  found (other than the one that may appear as part of a 7-bit ST),
  or if the sequence has been going on for too long (measured by the
  wall clock).

BUG=chromium:191050, Map Chrome OS top-row keys to function keys.
BUG=chromum-os:30792, beeps accumulate - leads to non stop beeping
BUG=chromum-os:35288, scroll-on-output doesn't appear to work
BUG=chromum-os:39645, Application keypad doesn't work properly

TEST=hterm_test.html 66/66 tests passed.

Change-Id: I65bf070e596d4fd5134d3c6d9e43b63f7b2def0e
Reviewed-on: https://gerrit.chromium.org/gerrit/45485
Reviewed-by: Dmitry Polukhin <dpolukhin@chromium.org>
Commit-Queue: Robert Ginda <rginda@chromium.org>
Reviewed-by: Robert Ginda <rginda@chromium.org>
Tested-by: Robert Ginda <rginda@chromium.org>

• hterm/.gitignore[Added - diff]
• hterm/bin/echo_changelog.sh[Deleted - diff]
• hterm/concat/hterm_deps.concat[diff]
• hterm/concat/hterm_resources.concat[diff]
• hterm/doc/changelog.txt[diff]
• hterm/js/hterm_keyboard_keymap.js[diff]
• hterm/js/hterm_scrollport.js[diff]
• hterm/js/hterm_terminal.js[diff]
• hterm/js/hterm_vt.js[diff]
• hterm/test_data/utf-8.txt[Added - diff]