issue1622: metricsview kerning, charview multichar trailing /.

allow trailing slash in charview, don't crash when altering kerning in
metricsview and there are multiple kern pairs visible with the current
value. mv: update other kern pairs when changing the current kern pair.
psread.c: Remove (originally) unreached code that broke autotrace

Commit b2a6cbb563d049a033508ec85fef583d14f38ac6 introduced the code
with check
   if (sp < sizeof(stack)/sizeof(stack[0]))

But as `stack` is a pointer, the result was comparing `sp < 0`, which
can never occur (sp >= 0). Hence this code block was never executed.

Commit a2c8bab1914abe2d6d1c012d8b57bf6444ce9e02 changed the code to be:
    if (sp < stacktop)

Which I can only guess is what it should be, *if* the code in the
code block worked with the current code.
Only search for paths inside the *g* node

Otherwise, we might get unwanted paths.
cleanup
comment
Merge pull request #1697 from fontforge/monkeyiq/2014/aug/1622p1

issue1622: metricsview kerning, charview multichar trailing /.
some lexer updates for metricsview and charview
Merge pull request #1699 from fontforge/monkeyiq/2014/aug/1622v2

some lexer updates for metricsview and charview
Merge pull request #1698 from jtanx/autotrace

psread.c: Remove (originally) unreached code that broke autotrace
1629: cv allow paging through chars without a unicode point.
Merge pull request #1700 from fontforge/monkeyiq/2014/aug/1629

1629: cv allow paging through chars without a unicode point.
1629: tested with glyph data in non unicode slots
Merge pull request #1701 from fontforge/monkeyiq/2014/aug/1629p2

1629: tested with glyph data in non unicode slots