Add drag and drop facility for installing languages.

Move a lang.po or lang.mo file to the Localize folder
(defined in defaults.config but set to lib/WeBWorK/Localize by default).

The name of the file will immediately appear in the General/Langauge
section of the Course Configuration page but it won't be possible
to switch to that language until an apache server restart has occurred.

Apparently mod_perl processes and stores the .po and .mo files so they
are not read on the fly.  Can this be changed?
Merge branch 'ww2.5.1.3' of https://github.com/mgage/webwork2-dev into ww2.5.1.3
Merge branch 'ww2.5.1.3' of https://github.com/openwebwork/webwork2-dev into ww-devel

Conflicts:
	VERSION
	conf/database.conf.dist
	conf/localOverrides.conf.dist
	htdocs/themes/math2/codemirror2
	htdocs/themes/ubc/codemirror2
	lib/WeBWorK/ContentGenerator/Instructor/ProblemGrader.pm
	lib/WeBWorK/URLPath.pm
Correct typo involving $dh

We need to have two handles $dh and $dh2 because we are dealing with two directories -- the theme directory
and the localization directory
Merge branch 'master' of https://github.com/jwj61/webwork2-dev into from_jj

Fixed conflicts and "m now merging.  Further work may need to be done.
Where should the file Browse.js go?  It's now in two places
What was intended for the modifications in SetMaker.js?  I'm not sure I made the right choices.

Conflicts:
	htdocs/js/lib/webwork/teacher/Browse.js
	lib/WeBWorK/ContentGenerator/instructorXMLHandler.pm
	lib/WebworkWebservice/LibraryActions.pm
	lib/WebworkWebservice/SetActions.pm
Merge branch 'master' of https://github.com/pstaabp/webwork2-dev into from_pstaab
save ProblemSets-1 in case we need it
Updated MathJax submodule to point to a v2.1 revision
New problems will now be saved with the default problem value (weight).  Also, stripped out some old debug statements.
Merge branch 'ww2.5.2' of https://github.com/mgage/webwork2-dev
correct $dh typo
fix typo in database.conf.dist
Fix typo in Config.pm

the file handles for searching the theme directory and the localize directory must be different
fix type in datbase.conf.dist
Add hack protecting against the possibility that userProblem doesn't exist (none was assigned?)
Add bugfixes from Geoff Goehle to ProblemGrader.pm
Add drag and drop facility for installing languages.

Move a lang.po or lang.mo file to the Localize folder
(defined in defaults.config but set to lib/WeBWorK/Localize by default).

The name of the file will immediately appear in the General/Langauge
section of the Course Configuration page but it won't be possible
to switch to that language until an apache server restart has occurred.

Apparently mod_perl processes and stores the .po and .mo files so they
are not read on the fly.  Can this be changed?
correct $dh typo
Merge branch 'ww2.5.1.3' of https://github.com/mgage/webwork2-dev into ww2.5.1.3

Conflicts:
	lib/WeBWorK/ContentGenerator/Instructor/Config.pm
update knowl.js to lastest version from AIM