Various fixes, updated default settings

Changes

• Added new web setting: ReadOnlyMode
• Added new column to the Trades page: Age
• Account data file is now backed up every time you start IntelliTrader
• Updated default settings
• Updated readme
• Improved exchange ticker initialisation and made it more robust
• Fixed profit calculation when holding dust
• Fixed the new exe launcher
• Fixed memory leak in ExchangeSharp
• Fixed division by zero when calculating price spread

Upgrading from v0.9.9.9

• Replace the bin folder