fix #1974 and #2413: center the line of interest

this change adds editor.centerOnCursor and a center option to
editor.setCursorPos and editor.setSelection and then uses that
API to center find/replace results, go to line results and
go to definition results for JS, CSS and HTML.
Use css height:auto to layout inline editors. Use CodeMirror wrapper element for inline editor height.
remove debug code
a couple of fixes based on review comments
changing the centering behavior to only center when the cursor is
either near the edges of the viewport or outside of it entirely.
This results in less hopping around when performing searches.
remove explicit height on inline text editor
remove direct calls to editor.centerOnCursor by incorporating centering
into the calls to setSelection in findNext and replace, per feedback
from pflynn
centerOnCursor now has clearer variable names
Add option to scroll inline widgets into view when added
simplify inline editor change handling. still need to address bugs and performance on a large delete.
remove extraneous editor refresh to improve performance
centerOnCursor adjusts to handle the menu bar area on top, and the status
bar adjustment is no longer hardcoded as a constant.
Fix InlineTextEditor close event handling and event handler removal.
code review comments
Always refresh host editor when size changes up or down.
Merge pull request #2475 from adobe/dangoor/cm3centering

fix #1974 and #2413: center the line of interest
Merge pull request #2476 from adobe/jasonsanjose/cmv3

Use css height:auto to layout inline editors, cmv3 wrapper element for inline editor height.