Fix encoding for copying LaTeX from clipboard

If we call tex2lyx on a temporary file created from the clipboard, the
file is always in utf8 encoding, without any temporary changes, even if it
contains encoding changing LaTeX commands. Therefore, we must tell tex2lyx
to use a fixed utf8 encoding for the whole file, and this is done using the
new latexclipboard format. Previously, tex2lyx thought the encoding was
latin1.
As a side effect, the -e option is now also documented in the man page.
Fix XeTeX export when using heb-article.layout

polyglossia is used by default and \make@lr is only defined
by babel. Modifying the preamble fixes XeTeX export and pdfTeX
continues to work.

See the following thread for more information:
  http://www.mail-archive.com/lyx-devel@lists.lyx.org/msg181220.html

Thanks to Enrico for the patch.
Fix export of Greek Intro manual with XeTeX

This is a workaround. Without this patch, export to .tex (XeTeX)
contains a sequence such as

  \begin{english}
  \begin{description}
  [omitted, but does not contain \end{description}]
  \end{english}

Thanks to Jürgen for the workaround.
Hebrew docs: move bookmarks inside of pdflatex if

This fixes XeTeX export of the Hebrew documents.
Fix bug 8880: do not try to validate custom value if it is disabled
Fix shortcut clash (bug #8878)

Patch by charley
Silence unwanted error popup on copying

The new HTML clipboard export could cause error message boxes on copying
data to the clipboard (bug #8866). These are now suppressed, like all other
errors which might occur for preparing the clipboard data.
Added self-sanity-check for presence of pcregrep, otherwise many (almost all) tests will fail.
Now run-tests.sh captures PROGRAM_SUFFIX from config.h, in order to use the correct .lyx folder name.
Fixing previous mess with git stash (apologies).
Back to development version
ctests: invert tests failing because of #8823
Do not try to validate custom value in VSpace dialog if it is disabled
Also consider main language in hasOnlyPolyglossiaLanguages() and hasPolyglossiaExclusiveLanguages()
Fix language issues in Argument read (#8471)
Fix regression of e02df14 (bug #8900)

In e02df14 the return type of doExport was changed from bool to ExportStatus.
All calls except this one were adjusted. This one did now fail because the
numercial value of ExportSuccess is 0.
Do not ignore literate programming errors
Fix wrong description screen font (bug #8869)

paper.cls formats the description label without bold, so LyX should do the
same on screen. Note that simply removing the Series line does not help,
because Description is already defined in some include.
Focus on custom line edit when custom is selected

Do so for the horizontal and vertical space dialogs.
List all exportable document formats in the Save As dialog, not only the selection from the export menu