restore devtools global shortcut

[maidh91]

• call the refresh function when cmd+r
• remove dead code globalReloaderActive
• note that there is a polling logic to check if devtools is unfocused, then unregister global shorcut (we need to unregister global shorcut so that it will not reload all running apps, should reload active app only)
  

  pear/gui/gui.js

  Lines 423 to 430 in c666cb5

  	// electron has absolutely no functioning blur event of any kind
  	// there is NO WAY in electron to react to devtools blur, so now this is happening:
  	let devtoolsBlurPolling = null
  	wc.on('devtools-opened', () => {
  	devtoolsBlurPolling = setInterval(() => {
  	if (wc.isDevToolsFocused() === false) this.menu.devtoolsReloaderUnlisten()
  	}, 150)
  	})