* Reenabled the mouseup event that was mysteriously disabled for an unknown amount of time. This made it difficult to report to the object mouse release event after it has been dragged and the mouse ended-up being positioned outside object's bounds.

* This now allows for very nice control over objects that are being grabbed.

* Mouse release sets doubleclick flag to -1 to differentiate itself from the regular mouse movement which also reports mouse press as 0.

* Allowed for glist_grab to be exclusive in respect to key presses and settable as such via the glist_grab call. See iemgui numbox for benefits of this implementation, described below.

* Completely reworked numbox logic with additional variables designed to improve code readability and disambiguate the x->x_gui.x_changed and x->x_gui.x_change.

* Rotated the order of event propagation to have glist_grab 1st and event bound objects second (e.g. key/keyname etc.). THIS IMPLEMENTATION SHOULD BE HEAVILY SCRUTINIZED TO MAKE SURE THERE ARE NO ADVERSE EFFECTS. Given the rapid release cycle I suggest adding it to the next release and then observing user feedback.

* The numbox now offers the following behavior:

1) click and drag and release (with or without shift which can be pressed at any time to toggle between fine +-0.01 and +-1 increments) which immediately changes the number value and outputs it. This kind of grab does not do exclusive keyboard grab and therefore allows keyboard to still propagate to other bound events.

2) click and immediately release enters the exclusive keyboard mode and makes the '>' appear to make the user aware of this. Here you can use arrows up/down with and without shift, press allowed keyboard keys (numbers, enter, delete, etc.) and edit the value accordingly. Pressing arrows always changes the last digit of the currently truncated number. Pressing enter commits the value and retains the focus for another 3 seconds unless user presses Esc or clicks outside the number box. If all the digits are erased the number implicity assumes 0.

3) clicking and immediately releasing without shift pressed to activate exclusive keyboard mode activates legacy/default behavior where entered text overwrites the existing (the cursor starts at the beginning and initially only has '>'). Doing the same with shift key puts the numbox in the append mode where one can continue adding to the previously committed number. This is even true if the displayed number is simply '+' or '-' due to it exceeding the number box width (not including decimals).

4) Values whenever committed are clipped to the object's min and max and reflected as such in the number object. If the object remains activated, the number is not clipped if it exceeds the object's length, but shows only last n visible digits. Upon removing focus (activation), it redraws from the beginning (if number of digits exceeds the width but does not exceed the min/max thresholds. Re-activating the object redraws it with the last digits visible.

* All glist_grab instances in externals should be taken care of and are, by default, not exclusive.

* Still TODO: checking if vanilla numbox is working ok. The rest of the objects shoould be unaffected.

* Lots of debugging stuff lying around.

* A significant rewrite of the prior iemgui numbox behavior to capitalize on the exclusive grab opportunity.

* migrating to Linux for debugging

Feature private abstractions test - Mac fixes

See merge request guillembartrina/purr-data!5

Merge branch 'feature_privateabstractions_test-cosmetic-fixes' into 'feature_privateabstractions_test'

Feature private abstractions test - cosmetic fixes

See merge request guillembartrina/purr-data!4

Minor touches to the private abstractions test branch.

See merge request guillembartrina/purr-data!3

* Label font is not any more erroneously affected by the resizing of the numbox

* The width is now more conservative and accurate

* When a new number was entered that exceeds the numbox width and was replaced by a + or a - and after it was refocused again with a shift pressed (thus entering the append mode), the + did not revert back to the entered number. Now it does (even though you only see the last n digits that fit the numbox--LATER: we may want to add a < or > at the beginning, letting the user know that there are more digits to the left. This however, with the current setup may not be as trivial as it seems, so we will keep it as-is for the time being until users report problems/dislike with the current mode of operation which is still way better than it used to be).

Following a discussion with Ico, make sure to apply the fix to actual
canvas class objects only, so that we do not exit temporary run mode
unless the user really clicked on a subpatch (or abstraction) object.

Fixes a residual regression with MR !528 (Findbox fixes) reported by
Joseph Gastelais, which causes temporary run mode to stick when opening
a subpatch using Alt-click (i.e., mouse click on the subpatch in
temporary run mode). Resolved using Jonathan's fake keyup trick.

If the declare object detects an unrecognized argument which isn't an
option symbol, it will print a weird-looking message complaining about
an empty flag. This commit makes it print a proper warning about an
unrecognized float argument instead.

*Addresses issue #449

'aggraef/purr-data-abstractionsaving-final-fix'