Fix #43 - Removed references to the activity in the handler of selected
custom server and added support through MyActivity to directly change
custom server on URL change.
Fix #44 - Changed how marker is restored if bad drag.
Fix #41 - Changed how server selector is triggered when pressing on
update server, when is necessary to download server list and saved to
preferences auto detected server.
Created javadoc for non trivial to understand functions of MainFragment
Merge pull request #52 from vreixo/issue50

Created javadoc for MainFragment
Merge pull request #47 from vreixo/issue41

Fix #41 - Solved issues with server selector
Merge pull request #46 from vreixo/issue44

Fix #44 - Changed how marker is restored if bad drag.
Merge pull request #45 from vreixo/issue43

Fix #43 - Problems selecting custom server