IText Glitches post 1.5.0 release

[gregtap]

From http://fabricjs.com/test/misc/itext.html.

The [a] which appears as a non capital char should have been capitalized. The whole list of styles seems to be off by one.

The same happens when selecting and replacing the content with a new character, the styles of preexisting chars is not kept and every styles get shifted.

[asturur]

I add it in the iText fixings for 1.5.0.1
With style problem when justify, space problem when justify.
In this case i think that just newlines are counted while shifting style

[asturur]

From http://fabricjs.com/test/misc/itext.html

An animation from my custom fork.

As soon as a new char is entered the bounding box is properly calculated. I tried to call setCoord and calcOffset without success.

[asturur]

I think that internal style change does not trigger a cache clearing.

[gregtap]

this._clearCache(); seems to be called, strange.
Memo: calling this._initDimensions(); did the trick.

[asturur]

i add #760