Correct Help Desk Search so it handles keywords and hash-colon-keyword lexemes.

Closes PR 13470.
add increase/decrease font size menu items (ala browsers)
avoid a wrapper on callbacks that get stored in a weak table

This fixes a bug in DrRacket where by changing the font size
would cause the line numbers to encroach on the space allotted
to the main text of the definitions window (or, if the font size
is getting smaller, make a large gap)
racket/gui: fix some contracts in docs
fix problem with the initial continuation prompt

(Got it wrong in 2f7d4b5e.)

Closes PR 13494
Add tests for subtyping -poly. Closes PR13510.
covered a missing case in the oc-status state machine
Replace <wbr> and <span class='mywbr'> </span> with zero-width-space.

The zero width space is a more robust way to add place to line-wrap,
according to: http://www.quirksmode.org/oddsandends/wbr.html

Closes PR 13305.
Amend comment.
fix rendering of example in Guide

closes PR 13517
Add raco show -d and showing package deps on failed remove
fix `syntax-local-submodules' in `expand' mode
fix context for `#%module-begin' form in a submodule
fix `syntax-local-module-exports' for submodules in expand mode
Windows: propagate system error text even with format commands

For example, error 193 now says "%1 is not a valid Win32 application.",
which is ugly but better than "Unknown error".
add for/set and it's varieties to the default prefs
fix submodule `expand' handling

Trying again for 4a0adb6a74.
fix error message
added unstable/macro-testing
change stxparse tests to use unstable/macro-testing