v11.17.0

• VaultPhase (None, Subscription, Investment, Redemption) and VaultShares.PhaseAt(LOVault, DateTime?, LedgerRules) are public (#298): the phase of a closed-ended vault as rippled's getVaultPhase decides it, with SubscriptionDate inside the subscription phase and RedemptionDate inside the redemption phase. A vault without SubscriptionDate stays in its subscription phase, one without RedemptionDate in its investment phase. PhaseAt returns None for a vault that is not closed-ended, without a time, and when LendingProtocolV1_1 is not enabled; Deposit, WithdrawAssets and RedeemShares refuse by the phase it returns
• Tests: TestUVaultShares checks PhaseAt on both sides of SubscriptionDate and RedemptionDate, with either date missing, with no time, with LendingProtocolV1_1 off, for an open-ended vault and one without VaultKind, and with local and unspecified times