Remove small warnings, simplify conditions/loops

src/org/sflphone/client/AccountEditionActivity.java

src/org/sflphone/client/AccountWizard.java

src/org/sflphone/history/HistoryCall.java

src/org/sflphone/history/HistoryEntry.java

src/org/sflphone/history/HistoryTimeModel.java

src/org/sflphone/model/BubblesView.java

src/org/sflphone/model/CallTimer.java

src/org/sflphone/model/account/AccountCredentials.java

src/org/sflphone/model/account/AccountDetail.java

src/org/sflphone/model/account/AccountDetailAdvanced.java

src/org/sflphone/model/account/AccountDetailBasic.java

src/org/sflphone/model/account/AccountDetailSrtp.java

src/org/sflphone/model/account/AccountDetailTls.java

src/org/sflphone/model/account/SRTPManager.java