issue/1871-reader-detail-illegal-state

Fix #1871 - in rare cases, storing very large text columns could result in an IllegalStateException when the row was read due to the 2MB size limit for Android's CursorWindow ( see [here](https://github.com/android/platform_frameworks_base/blob/master/core/res/res/values/config.xml#L946) and [here](https://github.com/android/platform_frameworks_base/blob/3bdbf644d61f46b531838558fabbd5b990fc4913/core/java/android/database/CursorWindow.java#L103) ).

This PR works around the problem by limiting the size of the string stored in the text column.